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3 years ago

The formula for the surface area of a cylinder is A=2πr(r+h).Find h if A=80π and r=5.

Mathematics

1 answer:

lesya [120]3 years ago

3 0

A=2πr(r+h)
80π=2π(5)(5+h)
80π=10π(5+h)
80π=50π + 10πh
30π=10πh
3=h

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What is the slope of a line that passes through (6,4) and (-1, 3)

pshichka [43]

Answer:

C) 1/7

Step-by-step explanation:

so idk what the formula is called but it looks like this:

y2-y1/x2-x1 and if you plug in the numbers then you'll get the answer

3 - 4/-1 - 6 = -1/-7 = 1/7

you can also switch the numbers your answer will always be the same

4 - 3/6 - (-1) = 1/7

so the answer is c

4 0

3 years ago

Type the correct answer in each box.

Vitek1552 [10]

Answer:

The coordinates of the point that is a reflection of Y(-4, -2) across the x-axis are ( -4,2).

The coordinates of the point that is a reflection of Y across the y-axis are ( 4,-2).

Step-by-step explanation:

Reflection across x-axis

The rule used for Reflection across x-axis is that y-coordinate becomes negated while x coordinate remains same.

So,

The coordinates of the point that is a reflection of Y(-4, -2) across the x-axis are ( -4,2).

Because according to definition, x-coordinate remains same, while y-coordinate is negated. So x-coordinate = -4, y-coordinate = 2

Reflection across y-axis

The rule used for Reflection across y-axis is that x-coordinate becomes negated while y coordinate remains same.

So,

The coordinates of the point that is a reflection of Y across the y-axis are ( 4,-2).

Because according to definition, y-coordinate remains same, while x-coordinate is negated. So x-coordinate = 4, y-coordinate = -2

7 0

3 years ago

Which coordinate pairs make the equation x-9y=12 true?

asambeis [7]

Answer:

(12,0) and (3, -1) and (0,-4/3)

Step-by-step explanation:

To find if a point makes an equation true, just substitute its x and y values in in the equation and simplify.

1) Let's test the point (12,0). Substitute 12 for x and 0 for y in the equation:

$x-9y=12\\(12)-9(0)=12\\12-0=12\\12=12$

12 does equal 12, so (12,0) makes the equation true.

2) Let's test the point (0, 12). Substitute 0 for x and 12 for y in the equation:

$x-9y=12\\(0)-9(12) = 12\\0-108 = 12\\-108 = 12$

However, -108 does not equal 12, so (0,12) does not make the equation true.

3) Let's test the point (3, -1). Substitute 3 for x and -1 for y in the equation:

$x-9y=12\\(3)-9(-1) = 12\\3 + 9 = 12\\12 = 12$

12 does equal 12, so (3, -1) makes the equation true.

4) Let's test the point (0, -4/3). Substitute 0 for x and -4/3 for y in the equation:

$(0) -9(-\frac{4}{3} ) = 12\\0 + \frac{36}{3} = 12\\0 + 12 = 12 \\12 = 12$

12 does equal 12, so (0, -4/3) makes the equation true.

8 0

3 years ago

$1500 at 9% for 2 years

kotykmax [81]

Answer:$270

Step-by-step explanation:

I=PRT

Interest=principal times rate times time

Principal=1500

Rate=9%=0.09

Time=2

I=1500 times 0.09 times 2

I=1500 times 0.18

I=270

Interest=270

Total is 1500+270=1770 total paid

8 0

3 years ago

The Ross family had 100 relatives at their big Thanksgiving dinner of all the guest nine he had French heritage 80 had English h

il63 [147K]

Hi, Deedee. I am quite confused with the numbers that you've given because they don't add up to 100. Nevertheless, if by 'this', you mean the Thanksgiving culture, then you would just count the English and the Native American heritage. This is because the first Thanksgiving dinner was shared between the English colonists and the Native American tribes.

I hope I was able to help you in a way. Have a good day.

8 0

2 years ago