Evaluate the expression for x = - 5 and y = 7 <br><br> 2x+3y-11

Readme [11.4K]

Answer:

k > 13

Step-by-step explanation:

$k+6 > 19\quad :\quad \begin{bmatrix}\mathrm{Solution:}\:&\:k > 13\:\\ \:\mathrm{Interval\:Notation:}&\:\left(13,\:\infty \:\right)\end{bmatrix}$

$\mathrm{Subtract\:}6\mathrm{\:from\:both\:sides}$

$k+6-6 > 19-6$

$\mathrm{Simplify}$

$k > 13$

Thus, the answer is k > 13

[RevyBreeze]

8 0

2 years ago

Subtract the rational expression 1/x^2-x-6 - x/x+2.

Aleksandr [31]

Answer:

Step-by-step explanation:

x² - x -6 = x² + 2x - 3x - 3*2

=x(x + 2) - 3(x + 2)

= (x + 2 )(x - 3)

$\frac{1}{x^{2}-x-6}+\frac{x}{x+2}=\frac{1}{(x +2 )(x - 3)}-\frac{x}{x + 2}\\$

$= \frac{1}{(x+2)(x-3)}-\frac{x(x-3)}{(x+2)(x-3)}\\\\=\frac{1-x(x-3)}{(x+2)(x-3)}\\\\=\frac{1-x^{2}+3x}{(x+2)(x-3)}\\\\$

4 0

2 years ago

Solve 4(-4x- 3)> 36

wariber [46]

Answer:

x=3

Step-by-step explanation:

Simplifying

4(4x + -3) = 36

Reorder the terms:

4(-3 + 4x) = 36

(-3 * 4 + 4x * 4) = 36

(-12 + 16x) = 36

Solving

-12 + 16x = 36

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '12' to each side of the equation.

-12 + 12 + 16x = 36 + 12

Combine like terms: -12 + 12 = 0

0 + 16x = 36 + 12

16x = 36 + 12

Combine like terms: 36 + 12 = 48

16x = 48

Divide each side by '16'.

x = 3

Simplifying

x = 3

8 0

3 years ago

Read 2 more answers

Nitrates are groundwater contaminants derived from fertilizer, septic tank seepage and other sewage. Nitrate poisoning is partic

o-na [289]

Answer:

a) $n=\frac{0.5(1-0.5)}{(\frac{0.02}{1.96})^2}=2401$

And rounded up we have that n=2401

b) $n=\frac{0.07(1-0.07)}{(\frac{0.02}{1.96})^2}=625.22$

And rounded up we have that n=626

And we see that if we have previous info about p the sample size varies a lot.

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

Solution to the problem

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 95% of confidence, our significance level would be given by $\alpha=1-0.95=0.05$ and $\alpha/2 =0.025$ . And the critical value would be given by:

$z_{\alpha/2}=-1.96, z_{1-\alpha/2}=1.96$

Part a

The margin of error for the proportion interval is given by this formula:

$ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$ (a)

And on this case we have that $ME =\pm 0.02$ and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2}$ (b)

Since we don't have prior information about the population proportion we can use ase estimator $\hat p =0.5$ . And replacing into equation (b) the values from part a we got:

$n=\frac{0.5(1-0.5)}{(\frac{0.02}{1.96})^2}=2401$

And rounded up we have that n=2401

Part b

For thi case the estimator for p is $\hat p =0.07$

$n=\frac{0.07(1-0.07)}{(\frac{0.02}{1.96})^2}=625.22$

And rounded up we have that n=626

And we see that if we have previous info about p the sample size varies a lot.

4 0

3 years ago

A couch, a love seat, and a chair cost $1565. The couch costs twice as much as the chair, and the love seat costs $400 more than

Brilliant_brown [7]

The answer to the question is 1565÷400=3.9125

6 0

3 years ago

Evaluate the expression for x = - 5 and y = 7 2x+3y-11