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4 years ago

Solve the following quadratic for the values x

Mathematics

2 answers:

mamaluj [8]4 years ago

8 0

Answer:

x² + 6x - 27 = 0

x² + 9x - 3x - 27 = 0

x ( x + 9 ) - 3 ( x + 9 ) = 0

( x + 9 ) ( x - 3 ) = 0

Thus ,

x = -9 or x = 3

I hope it helps you

#Indian : )

mestny [16]4 years ago

4 0

${x}^{2} + 6x - 27 = 0 \\ D= {6}^{2} - 4 \times ( - 27) = 36 + 108 = 144 = {12}^{2} \\ x_1= \dfrac{ - 6 + 12}{2} = 3 \\ x_2= \dfrac{ - 6 - 12}{2} = - 9$

Answer: x=3; x=-9

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What is the value of x in the equation -6x = 5x+ 22?<br> -22<br> 0 -2<br> 02<br> O 22

Ivahew [28]

Answer:

x = -2

Step-by-step explanation:

Solve -6x = 5x + 22

add 6x to both sides

0 = 6x + 5x + 22

0 = 11x + 22

11x = -22

x = -22/11

x = -2

3 0

3 years ago

suppose X and Y are independent random variables, both with normal distributions. If X has a mean of 45 with a standard deviatio

djyliett [7]

Answer:

0.9772 = 97.72% probability that a randomly generated value of X is greater than a randomly generated value of Y

Step-by-step explanation:

When the distribution is normal, we use the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this question:

$\mu_X = 45, \sigma_X = 4, \mu_Y = 35, \sigma_Y = 3$

What is the probability that a randomly generated value of X is greater than a randomly generated value of Y

This means that the subtraction of X by Y has to be positive.

When we subtract two normal variables, the mean is the subtraction of their means, and the standard deviation is the square root of the sum of their variances. So

$\mu = \mu_X - \mu_Y = 45 - 35 = 0$

$\sigma = \sqrt{\sigma_X^2+\sigma_Y^2} = \sqrt{25} = 5$

We want to find P(X > 0), that is, 1 subtracted by the pvalue of Z when X = 0. So

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{0 - 10}{5}$

$Z = -2$

$Z = -2$ has a pvalue of 0.0228

1 - 0.0228 = 0.9772

0.9772 = 97.72% probability that a randomly generated value of X is greater than a randomly generated value of Y

4 0

3 years ago

Help me out please!!!!

DedPeter [7]

Answer:

Answer (e)

Step-by-step explanation:

Note that this graph has a zero at x = 1 and a vertical asymptote at x = -4. Only Answer (e) corresponds to that. Try letting x = 1. y is zero, correct? Try letting x = -4. y is undefined, correct?

7 0

3 years ago

What is a solutions of x^2-2x+10=0?

Debora [2.8K]

Answer:

x = 1± 3i

Step-by-step explanation:

x^2-2x+10=0

We can complete the square to solve by subtracting 10 from each side

x^2-2x+10-10=-10

x^2 -2x = -10

We need to add (2/2) ^2 to each side or 1

x^2 -2x+1 = -10 +1

x^2 -2x+1 = -9

The left side factors into (x- (2/2) ) ^2

(x-1) ^2 = -9

Take the square root of each side

sqrt((x-1) ^2 =± sqrt(-9)

x-1 = ±sqrt(-1) sqrt(3)

Remember the sqrt(-1) = i

x-1 = ± 3i

Add 1 to each side

x-1+1 = 1± 3i

x = 1± 3i

8 0

3 years ago

The sum of twice a number and seven is twenty five

Mama L [17]

9

Because 9x2 is 18+7=25

3 0

3 years ago