Therefore, the variance of the time it takes for someone to finish a bowl of ramen is 4.6875.
Given, The moment generating function of the time it takes for someone to finish a bowl of ramen is
M(t)= 1/ (1−0.05t)1,t<0.05 We have to find the variance of the time it takes for someone to finish a bowl of ramen.
The variance of the random variable can be calculated by the formula Variance = M''(0) - [M'(0)]^2 where M(t) is the moment generating function of the random variable M'(t) is the first derivative of M(t)M''(t) is the second derivative of M(t)
We need to find M''(t) and M'(t)M(t) = 1/(1 - 0.05t)M'(t) = [0.05/(1 - 0.05t)^2]M''(t) = [0.1/(1 - 0.05t)^3] Now, at t = 0, M(0) = 1, M'(0) = 1.25, M''(0) = 6.25 Variance = M''(0) - [M'(0)]^2 Variance = 6.25 - (1.25)^2 Variance = 6.25 - 1.5625 Variance = 4.6875
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Given: The time it takes for someone to finish a bowl of ramen can be modeled by a random variable with the following moment generating function: M(t)= 1/ (1−0.05t)1,t<0.05. The variance of the time it takes for someone to finish a bowl of ramen is 400.
The moment generating function of a random variable is defined as [tex]$M(t) = \mathbb{E}(e^{tX})$[/tex] for all t in an open interval around 0 which X is a random variable.
We are given that the moment generating function of the random variable T is given by:
[tex]$$M(t)= \frac{1}{1-0.05t} ,\ t < 0.05$$[/tex]
The [tex]$n^{th}$[/tex] derivative of M(t) at 0 is given by:
[tex]$$\frac{d^n}{dt^n} M(t) \biggr|_{t=0} = \mathbb{E}(X^n)$$[/tex]
We differentiate $[tex]M(t)$[/tex] with respect to $t$ to get [tex]$$M'(t) = \frac{0.05}{(1 - 0.05t)^2}$$[/tex].
Differentiating [tex]$M'(t)$[/tex] with respect to [tex]$t$[/tex] we get [tex]$$M''(t) = \frac{2(0.05)^2}{(1-0.05t)^3}$$[/tex].
Differentiating [tex]$M''(t)$[/tex] with respect to [tex]$t$[/tex] we get [tex]$$M'''(t) = \frac{6(0.05)^3}{(1-0.05t)^4}$$[/tex].
Substituting t = 0, we get [tex]$$M'(0) = \frac{1}{0.05} = 20$$[/tex]
[tex]$$M''(0) = \frac{2}{(0.05)^3} = 800$$[/tex]
[tex]$$M'''(0) = \frac{6}{(0.05)^4} = 4800$$[/tex]
Using the following formula to calculate the variance of X: [tex]$$Var(X) = \mathbb{E}(X^2) - [\mathbb{E}(X)]^2$$[/tex], where [tex]$$\mathbb{E}(X^2) = M''(0) = 800$$[/tex].
[tex]$$[\mathbb{E}(X)]^2 = [M'(0)]^2 = 400$$[/tex]
Hence, we get:$$Var(X) = 800 - 400 = \boxed{400}$$.
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A snow removal service in Minnesota is deciding to purchase a new snow removal machine. If they dont purchase the machine, they will make $20,000 if the winter is mild, 530,000 il it is typical, and $50,000 the winter is severe. If they purchase the machine, their profits for these conditions will be $30,000, 535,000 and $40,000, respectively. The probability of a mild winter is 0.3. a typical winter is 0.5 and a severe winter is 0.2. What is the EMV for no machine? 32000 34500 35000 31000
The Europay, Mastercard and Visa (EMV) for not purchase the snow removal machine is $31,000.
The expected monetary value (EMV) for not purchasing the snow removal machine is $31,000. This value is calculated by multiplying the probabilities of each winter condition by the corresponding profits and summing them up. The probabilities for a mild winter, typical winter, and severe winter are 0.3, 0.5, and 0.2, respectively.
The profits for each condition without the machine are $20,000, $530,000, and $50,000. By multiplying each profit by its probability and adding them together, we get the EMV of $31,000 for not purchase the machine.
In detail, the EMV is calculated as follows:
EMV = (Probability of Mild Winter * Profit for Mild Winter) + (Probability of Typical Winter * Profit for Typical Winter) + (Probability of Severe Winter * Profit for Severe Winter)
EMV = (0.3 * $20,000) + (0.5 * $530,000) + (0.2 * $50,000)
EMV = $6,000 + $265,000 + $10,000
EMV = $31,000
Therefore, the EMV for not purchasing the snow removal machine is $31,000.
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The points (x, 3) and (-1, -4) lie on the same line. If the slope of the line is 1, what is
the value of x?
A-3
B 1
C 6
D-6
Answer:
C) 6
Step-by-step explanation:
use slope formula:
(-4 - 3) / (-1 - x) = 1
cross-multiply:
-7 = -1 - x
-6 = -x
6 = x
For the following regression model Y = α + βX + u
-Explain how we can test if we adopt the wrong functional forms
of independent variables?
In order to test if we have adopted the wrong functional forms of independent variables in a regression model Y = α + βX + u, we can use diagnostic plots of the residuals.
Residuals are the differences between the actual values of the dependent variable and the predicted values of the dependent variable. We can plot the residuals against the independent variables to check if there is any functional form that has not been captured by the model, which would indicate that the model has adopted the wrong functional form of independent variables.
If there is no pattern in the residuals when plotted against the independent variables, then it can be concluded that the model has captured the correct functional form of the independent variables. However, if there is a pattern in the residuals, it would indicate that there is some functional form that has not been captured by the model, and we would need to explore different functional forms of the independent variables to see which one fits the data better. This can be done by using different functional forms of the independent variables, such as polynomial, logarithmic, exponential, etc., and comparing the results using various statistical tests.
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If the residuals are normally distributed, then it suggests that the functional form of the independent variable is correct. If they are not, then it suggests that the functional form of the independent variable is incorrect.Overall, it is important to test for the functional forms of independent variables to ensure that the results of the regression model are unbiased and accurate.
In a regression model, it is important to make sure that the functional forms of the independent variables are correct. If they are not, the results of the model may be biased and incorrect. There are several ways to test if the functional forms are correct or not. Below are some of the methods:Plotting the residuals against the independent variable: If the functional form of the independent variable is correct, then the residuals should be randomly distributed around zero, without showing any patterns. If there are patterns in the residuals, then it suggests that the functional form is incorrect. Testing for linearity: One way to test for linearity is by including the square or cubic terms of the independent variable in the model and testing their significance. If the squared or cubic term is significant, then it suggests that the functional form of the independent variable is incorrect. Testing for additivity: One way to test for additivity is by including interaction terms between the independent variables and testing their significance. If the interaction term is significant, then it suggests that the functional form of the independent variable is incorrect. Testing for normality: One way to test for normality is by examining the normal probability plot of the residuals.
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Han and Andre were comparing the miles they ran during one week of cross country practice Hantan 12 which was three times as much as Andre
How many they run together during the one week
Answer:
I don't know.
Step-by-step explanation:
M is the midpoint of PQ. PM = 7x + 8 and MQ = 5x+ 20. Find the value of x.
Two discrete random variables have a joint PMF as described in the following table. PM (m, n) m = 1 2 m = 3 n=1 1/5 7/45 1/9 n = 2 8/45 4/45 2/45 n = 3 2/15 1/15 1/45 (a) Find the marginal PDFs, P(m) and Py(n). Р (b) Find Pr(N=1|M= 2). (c) Find Pr(MEN). (d) Find Pr(M>N).
a. P(1) = 0.3556, P(2) = 0.3111, P(3) = 0.0444; Py(1) = 0.5333, Py(2) = 0.4444, Py(3) = 0.1222 b. P(N = 1 | M = 2) ≈ 0.2574 c.P(M = 2, N = 3) ≈ 0.038 d. Pr(M>N) = 0.5333.
a. The marginal probability function of m is given by P(m) = Σn P(m, n) and that of n is given by P(n) = Σm P(m, n).
Thus, the marginal PDFs are: P(1) = 1/5 + 8/45 + 2/15 = 0.3556 P(2) = 7/45 + 4/45 + 1/15 = 0.3111
P(3) = 1/9 + 2/45 + 1/45 = 0.0444 P(1) + P(2) + P(3) = 1 Py(1) = 1/5 + 7/45 + 2/15 = 0.5333
Py(2) = 8/45 + 4/45 + 1/15 = 0.4444 Py(3) = 2/15 + 1/15 + 1/45 = 0.1222 Py(1) + Py(2) + Py(3) = 1.
b. We need to find P(N = 1 | M = 2).
From the joint probability distribution table, we can see that P(N = 1, M = 2) = 8/45. P(M = 2) = 0.3111.
Using the conditional probability formula, P(N = 1 | M = 2) = P(N = 1, M = 2)/P(M = 2) = 8/45 ÷ 0.3111 ≈ 0.2574
c. We need to find the probability that M = E and N = N.
Since the two random variables are independent, we can simply multiply their probabilities: P(M = E, N = N) = P(M = E) × P(N = N).
The probability distribution of M is given by: M=1 with probability 0.3556 M=2 with probability 0.3111 M=3 with probability 0.0444
The probability distribution of N is given by: N=1 with probability 0.5333 N=2 with probability 0.4444 N=3 with probability 0.1222
Therefore, P(M = 2, N = 3) = P(M = 2) × P(N = 3) = 0.3111 × 0.1222 ≈ 0.038
d. We need to find P(M > N).
There are three possible pairs of values for (M, N) such that M > N: (M = 2, N = 1), (M = 3, N = 1), and (M = 3, N = 2).
The probabilities of these pairs of values are: P(M = 2, N = 1) = 1/5 P(M = 3, N = 1) = 1/9 P(M = 3, N = 2) = 1/15
Therefore, P(M > N) = P(M = 2, N = 1) + P(M = 3, N = 1) + P(M = 3, N = 2) = 1/5 + 1/9 + 1/15 = 0.5333.
Answer: a. P(1) = 0.3556, P(2) = 0.3111, P(3) = 0.0444; Py(1) = 0.5333, Py(2) = 0.4444, Py(3) = 0.1222 b. 0.2574 c. 0.038 d. 0.5333
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An analyst Is forecasting net Income for Excellence Corporation for the next fiscal year. Her low-end estimate of net Income is $261,000, and her high-end estimate is $312,000. Prior research allows her to assume that net income follows a continuous uniform distribution. The probability that net income will be greater than or equal to $299,500 Is Multiple Choice 75.5% O o 24.5% 84.4% O O 41.6%
A net income forecast for Excellence Corporation is made by an analyst for the next fiscal year. Low-end estimate of net income is $261,000High-end estimate is $312,000. Net income follows a continuous uniform distribution. To find: The probability that net income will be greater than or equal to $299,500. In order to solve the problem, we need to calculate the probability that net income will be between $299,500 and $312,000.
Then, we will subtract it from the probability that net income will be between $261,000 and $312,000. This difference will give us the required probability. P(261000 <= X <= 312000) = (312000-261000) / (312000-261000) = 0.2P(299500 <= X <= 312000) = (312000-299500) / (312000-261000) = 0.55P(X >= 299500) = P(299500 <= X <= 312000) - P(261000 <= X <= 312000) = 0.55 - 0.2= 0.35 or 35%.
Thus, the probability that net income will be greater than or equal to $299,500 is 35%. Therefore, the answer is: 24.5%.
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A trapezoid has bases of lengths 38 and 52. Find the trapezoids area if it’s height is 8.
Answer:
360
Step-by-step explanation:
3. Which property justifies rewriting
2r-7x
*(2-7) ?
OA. Associative property of multiplication
OB. Distributive property
OC. Commutative property of multiplication
O D. Associative property of addition
I NEED HELP I WILL GIVE BRANLIEST REAL ANSWERS ONLY PLZZZ!!!!!I NEED HELP I WILL GIVE BRANLIEST REAL ANSWERS ONLY PLZZZ!!!!!I NEED HELP I WILL GIVE BRANLIEST REAL ANSWERS ONLY PLZZZ!!!!!I NEED HELP I WILL GIVE BRANLIEST REAL ANSWERS ONLY PLZZZ!!!!!I NEED HELP I WILL GIVE BRANLIEST REAL ANSWERS ONLY PLZZZ!!!!!I NEED HELP I WILL GIVE BRANLIEST REAL ANSWERS ONLY PLZZZ!!!!!I NEED HELP I WILL GIVE BRANLIEST REAL ANSWERS ONLY PLZZZ!!!!!
Answer:
Step-by-step explanation:
To find each probability you will state the probability of the first event happening and multiply it by the chance of the second event happening.
P(2 Nickels): 6/10 x 5/9 = 30/90 (1/3 chance)
P(2 Dimes): 4/10 x 3/9 = 12/90 (4/30 chance)
P(1 nickel and 1 dime): 6/10 x 4/9 = 24/90 (8/30 chance)
I hope this helps :D
Find the derivative of f(x) = 8x + 4 at x = 9. (6 points)
Answer:
f(x) = 76
Step-by-step explanation:
All you do is plug-in for x: (x = 9)
f(x) = 8x + 4
f(x) = 8(9) + 4
f(x) = 72 + 4
f(x) = 76
A brand of uncooked spaghetti comes in a box that is a rectangular prism with a length of 9 inches, a width of 2 inches, and a height of 1 1/2 inches. What is the surface area of the box?
Answer:
SA = 157 in²Steps:
SA = 2LW + 2WH + 2LH
SA = 2(9×2) + 2(2×11/2) + 2(9×11/2)
SA = 2×18 + 2×22/2 + 2×99/2
SA = 36 + 22 + 99
SA = 157 in²
If 3 inches represents 25 feet on a scale
drawing, how long will a line segment be
that represents 15 feet?
Answer:
1.8 inches
Step-by-step explanation:
1. find the # of inches that represents 1 foot.
3/25 = 0.12in
2. to find the length of the line segment that represents 15 feet, multiply 0.12 inches by 15.
0.12*15 = 1.8in
You measure a wound to be 2.5 inches long. How many millimetres long is the wound? Round to the nearest tenth.
You measure the depth of a wound to be 0.25 inches. How many millimetres is this? Round to the nearest whole number.
(a) If you measure a wound to be 2.5 inches long, the corresponding length in millimeters is 63.5 mm.
(b) If you measure the depth of a wound to be 0.25 inches, the corresponding length in millimeters is 6.35 mm.
What is the measure of the lengths?If you measure a wound to be 2.5 inches long, the corresponding length in millimeters is calculated as follows;
1 in = 25.4 mm
2.5 in = ?
? = 2.5 x 25.4 mm
? = 63.5 mm
If you measure the depth of a wound to be 0.25 inches, the corresponding length in millimeters is calculated as follows;
1 in = 25.4 mm
0.25 in = ?
? = 0.25 x 25.4 mm
? = 6.35 mm
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please help, tysm if you do
Answer: It’s 3
Step-by-step explanation:
Hoped I help :)
Mhanifa please help im almost done :)
Answer:
19)
9/4 = (r - 10)/r9r = 4(r - 10)9r = 4r - 405r = -40r = -820)
(x + 6)/x = 10/710x = 7(x + 6)10x = 7x + 423x = 42x = 1421)
(n - 9)/(n + 5) = 7/47(n + 5) = 4(n - 9)7n + 35 = 4n - 363n = -71n = -71/322)
6/(b + 9) = 4/(b + 5)6(b + 5) = 4(b + 9)6b + 30 = 4b + 362b = 6b = 323)
8/3 = (v - 9)/(7v + 4)8(7v + 4) = 3(v - 9)56v + 32 = 3v - 2753v = - 59v = -59/5324)
8/(5x - 4) = 6/(x + 5)8(x + 5) = 6(5x - 4)8x + 40 = 30x - 2422x = 64x = 64/22x = 32/11The perimeter of a rectangular field is 298 yards. If the width of the field is 63 yards, what is its length?
Answer:
The length is 86 yards.
Step-by-step explanation:
63 is the width so,
63 + 63 = 126
Now subtract this from the total perimeter,
298 - 126 = 172
and divide by 2 because there are sides with the same length
172/2 = 86
The length is 86.
9.20. set s = 2z = {2x : x ∈ z}, the set of even integers. prove that s is equicardinal with z.
To prove that the set S = 2Z = {2x : x ∈ Z}, the set of even integers, is equicardinal with Z, the set of all integers, we need to show that there exists a one-to-one correspondence (bijection) between the two sets.
A one-to-one correspondence between two sets exists if every element of one set is paired with a unique element from the other set, and vice versa.
Let's define a function f: Z -> S such that f(x) = 2x for every x ∈ Z.
This function assigns each integer x from Z to its corresponding even integer 2x in S.
To prove that f is a bijection, we need to show that it is both injective (one-to-one) and surjective (onto).
Injectivity: Suppose f(a) = f(b) for some a, b ∈ Z. Then, 2a = 2b. Dividing both sides by 2, we get a = b. Hence, f is injective.
Surjectivity: For every y ∈ S, y = 2x for some x ∈ Z. Choosing x = y/2, we have f(x) = 2x = y. Therefore, f is surjective.
Since f is both injective and surjective, it is a bijection. Thus, S and Z are equicardinal sets.
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A part manufactured at a factory is known to be 12.05 cm long on average, with a standard deviation of 0.119. One day you suspect that that the part is coming out a little longer than usual, but with the same deviation. You sample 19 at random and find an average length of 12.25. What is the z-score which would be used to test the hypothesis that the part is coming out longer than usual?
Z-score is used to test the hypothesis that the part is coming out longer than usual. Z-score is defined as the number of standard deviations away from the mean.
It is calculated using the formula z = (x - μ) / σ, where x is the sample mean, μ is the population mean, and σ is the population standard deviation. In the given problem, the population mean is μ = 12.05 cm and the population standard deviation is σ = 0.119 cm. The sample mean is x = 12.25 cm. The sample size is n = 19.
Therefore, the formula to calculate the z-score is Z = (x - μ) / (σ / √n) Substituting the values, we get z = (12.25 - 12.05) / (0.119 / √19) ≈ 6.586Therefore, the z-score which would be used to test the hypothesis that the part is coming out longer than usual is approximately 6.586.
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A rectangle has a length of 2x + 1 and a width
of 5x - 4. Which expression best describes the
area of the rectangle?
F 7x - 3
H 10x2 – 3x - 4
J 10x2 + 13x - 4
G 14x - 6
Answer:
H
Step-by-step explanation:
The rectangle has a length of (2x + 1) and a width of (5x - 4).
And we want to select the expression that represents the rectangle's area.
Recall that a rectangle's area is simply its length multiplied by its width. Thus:
[tex]A=(2x+1)(5x-4)[/tex]
Expand by distributing:
[tex]A=(2x+1)(5x)+(2x+1)(-4)[/tex]
Distribute:
[tex]A=(10x^2+5x)+(-8x-4)[/tex]
Simplify:
[tex]A=10x^2-3x-4[/tex]
Hence, our answer is H.
[x-2]/4=[3x-7]/10 its x-2 dived by 4 not 2/4 same with other side
Answer:
x = 4
Step-by-step explanation:
Given
[tex]\frac{x-2}{4}[/tex] = [tex]\frac{3x-7}{10}[/tex] ( cross- multiply )
4(3x - 7) = 10(x - 2) ← distribute parenthesis on both sides )
12x - 28 = 10x - 20 ( subtract 10x from both sides )
2x - 28 = - 20 ( add 28 to both sides )
2x = 8 ( divide both sides by 2 )
x = 4
A pool has a length that is 3 times the width. Write the algebra radical value of the corner to corner distance
Answer:
The distance between corner to corner is equal to √10 times the width.
D = √10*W
Step-by-step explanation:
For a rectangle of length L and width W, the distance between two opposite corners can be calculated if we use the Pythagorean's theorem, where we can think on the length as one cathetus, the width as another cathetus and the diagonal as the hypotenuse.
Then the length of the diagonal is:
D^2 = L^2 + W^2
D = √( L^2 + W^2)
In this case we know that the length is 3 times the width, then:
L = 3*W
Replacing this in the equation for the diagonal we have:
D = √( (3*W)^2 + W^2) = √( 9*W^2 + W^2)
D = √( 10*W^2) = √10*√W^2 = √10*W
D = √10*W
The distance between corner to corner is equal to √10 times the width.
I need help thank you
Answer: 4x-3
Step-by-step explanation: use the slope formula to calculate the slope, then add the y-int to the equation and ur done hope this helps
Suppose Lucy want to make sure that when she reaches into her drawer, she is certain to take out enough gloves so that she will have one matching pair to wear. HOW MANY GLOVES MUST SHE TAKE?
Answer:
its 2
Step-by-step explanation:
I have consulted many nice people ( my idiot friends) they all say 2 good luck
The person who answers has an explanation that doesn't have a link, and isn't incorrect gets brainiest. Ok here is the question "What are the first 30 characters in pi aka ~3.141592653589793238462643383 is all I remember."
Answer:
3.14152628283829299348473929
Janna is buying a netbook with a flash drive. The total cost c will include the price p of the netbook plus $12.50 for the flashdrive. Which is the dependent variable?
Evaluate 3f(2) what is it
Answer:
the eanswer should be 12
Step-by-step explanation:
i took the test
One of the legs of a right triangle measures 12 cm and the other leg measures 13 cm find the measure of the hypotenuse if necessary round the nearest 10th
Answer:
17.7 cm
Step-by-step explanation:
One of the legs of a right triangle measures 12 cm and the other leg measures 13 cm find the measure of the hypotenuse if necessary round the nearest 10th
To find the Hypotenuse of a right angle triangle, we solve using Pythagoras Theorem
Hypotenuse ² = Opposite ² + Adjacent ²
Hypotenuse = √Opposite ² + Adjacent ²
Opposite = 12 cm
Adjacent = 13 cm
Hence,
Hypotenuse = √12² + 13²
= √144 + 169
= 17.691806013 cm
Approximately = 17.7 cm
Therefore, the measure of the Hypotenuse is 17.7 cm
People were polled on how many books they read the previous year. Initial survey results indicate that s = 13.6 books Complete parts (a) through (d) below. Click the icon to view a partial table of critical values. (n) How many subjects are needed to estimate the mean number of books read the previous year within six books with 90% confidence? This 90% confidence level requires subjects. (Round up to the nearest subject.)
Approximately 48 subjects are needed to estimate the mean number of books read the previous year within six books with 90% confidence.
To estimate the mean number of books read the previous year within a certain margin of error, we need to determine the sample size required. In this case, we want to estimate the mean with a 90% confidence level and a margin of error of ±6 books.
The formula to calculate the required sample size is given by:
n = (Z * σ / E)²Where:n = sample sizeZ = z-value (corresponding to the desired confidence level)σ = standard deviation (unknown in this case)E = margin of errorSince the standard deviation is unknown, we can use the initial survey result, s = 13.6 books, as an estimate for σ. However, this may result in a larger sample size than necessary.
Referring to the critical values table, we find the z-value corresponding to a 90% confidence level is approximately 1.645. Plugging in the values into the formula:
n = (1.645 * 13.6 / 6)²n ≈ 47.57Since the sample size must be a whole number, we round up to the nearest subject. Therefore, approximately 48 subjects are needed to estimate the mean number of books read the previous year within six books with 90% confidence.
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Complete the Square of the quadratic equation in standard form: ax2 + bx + c Treat this like a literal equation where you are solving for x by completing the square. To get started, write the equation in the form: x2 + bx = ?
Answer:
x = [-b ±√(b² - 4ac)]/2a
Step-by-step explanation:
ax² + bx + c = 0
dividing through by a, we have
ax²/a + bx/a + c/a = 0
x² + bx/a + c/a = 0
x² + bx/a = -c/a
we now add th square of half the coefficient of x to both sides, thus
x² + bx/a + (b/2a)² = -c/a + (b/2a)²
simplifying the left hand side and right hand side, we have
(x + b/2a)² = -c/a + b²/4a²
re-arranging, we have
(x + b/2a)² = b²/4a² - c/a
taking L.C.M of the right hand side, we have
(x + b/2a)² = (b² - 4ac)/4a²
taking square-root of both sides, we have
√(x + b/2a)² = ±√[(b² - 4ac)/4a²]
x + b/2a = ±√(b² - 4ac)/2a
So, x = -b/2a ±√(b² - 4ac)/2a
taking the L.C.M of the right hand side, we have
x = [-b ±√(b² - 4ac)]/2a