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3 years ago

If y is directly proportional to x and y = -15 when x=3 find the value of y when x is 20?

1 answer:

5 0

Answer: y = 2

Explanation:

When x = 3, y = -15

And x and y are directly proportional.

thus x + k ==> y + k

when x = 3 + 17 ==> y = -15 + 17

=> x = 20 ==> y = 2

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Find the equation of the line that goes through (-8,11) and is perpendicular to x= - 15. Write the equation in the form x = a, y

galben [10]

Answer:

y=11

Step-by-step explanation:

Hi there!

We want to find the equation of the line that passes through the point (-8, 11) and is perpendicular to x=-15

If a line is perpendicular to another line, it means that the slopes of those lines are negative and reciprocal; in other words, the product of the slopes is equal to -1

The line x=-15 has an undefined slope, which we can represent as 1/0, which is also undefined.

To find the slope of the line perpendicular to x=-15, we can use this equation (m is the slope):

$m_1*m_2=-1$

$m_1$ in this instance would be 1/0, so we can substitute it into the equation:

$\frac{1}{0} *m_2=-1$

Multiply both sides by 0

$m_2=0$

So the slope of the new line is 0

We can substitute it into the equation y=mx+b, where m is the slope and b is the y intercept:

y=0x+b

Now we need to find b:

Since the equation passes through the point (-8,11), we can use its values to solve for b.

Substitute -8 as x and 11 as y:

11=0(-8)+b

Multiply

11=0+b, or 11=b

So substitute into the equation:

y=0x+11

We can also write the equation as y=11

Hope this helps!

5 0

3 years ago

Which is a graph for the inequality m<(or equal to)-2?

brilliants [131]

Answer:

cool

Step-by-step explanation:

5 0

3 years ago

At 95% confidence, how large a sample should be taken to obtain a margin of error of 0.03 for the estimation of a population pro

Gnom [1K]

Answer:

A sample of 1068 is needed.

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the zscore that has a pvalue of $1 - \frac{\alpha}{2}$ .

The margin of error is:

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

95% confidence level

So $\alpha = 0.05$ , z is the value of Z that has a pvalue of $1 - \frac{0.05}{2} = 0.975$ , so $Z = 1.96$ .

At 95% confidence, how large a sample should be taken to obtain a margin of error of 0.03 for the estimation of a population proportion?

We need a sample of n.

n is found when M = 0.03.

We have no prior estimate of $\pi$ , so we use the worst case scenario, which is $\pi = 0.5$

Then

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

$0.03 = 1.96\sqrt{\frac{0.5*0.5}{n}}$

$0.03\sqrt{n} = 1.96*0.5$

$\sqrt{n} = \frac{1.96*0.5}{0.03}$

$(\sqrt{n})^{2} = (\frac{1.96*0.5}{0.03})^{2}$

$n = 1067.11$

Rounding up

A sample of 1068 is needed.

8 0

3 years ago

HELP IF RIGHT I WILL MARK BRAINLIEST!!!! TRUST

DENIUS [597]

Answer:

I came up with 412cm^2

Step-by-step explanation:

10*12+(12*2)2+(10*2)2+6*8+(8*3)2+(6*3)2+(12*10-6*8)

6 0

3 years ago

Please help me lol

Svetach [21]

Answer:

ATP is made for the instance so you don't run out of energy. Fat stores glycogen which can be broken down into glucose and turned into ATP. I don't know what you're asking specifically thought it's a bit jumbled.

6 0

3 years ago

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