Question

Quick help w/ two multiple choice questions? (Q's Inside) [Will MEDAL & FAN]

Answer 1

@UnkleRhaukus quick help?

Answer 2

Can you find the area of the whole circle?

Answer 3

The blue region is 3/4 of the whole circle, plus a triangle

Answer 4

1017.88 Is what I got as the area of the whole circle

Answer 5

good, so what is that area of 3/4 of the circle?

Answer 6

So I would do 1017.88 divided by 4 which is 254.47 then multiply that by 3 and get 763.41-- Thats 3/4 of 1017.88

Answer 7

yes, that is right, but for this question you should leave your answer in terms of pi

\[A_\text{whole circle} = \pi r^2= \pi\times18^2=\pi\times 324\approx1017.88\]
\[A_{3/4\text{ circle}} =\frac34\times\pi\times 324=243\pi\approx763.14\]

Answer 8

Now we need to find the area of the triangle.

Fortunately, the triangle is right-angled...

Answer 9

\[A_\text{triangle}=\tfrac12bh\]

In our case, \(b=h=r=18\)

Answer 10

So 1/2 * 18?

Answer 11

no,
1/2 * 18 *18

Answer 12

1/2 * 18 * 18 = 162

Answer 13

right,

Answer 14

So (243pi + 162) ft^2
or
(243pi - 162) ft^2

Answer 15

And the total area of the blue region is the sum of the 3/4 circle, and the triangle

i.e.\[A_\text{blue region} = A_{3/4\text{ circle}} + A_\text{triangle}\\
\qquad\qquad=%243\pi+162
\]

Answer 16

I choose letter A, correct?

Answer 17

Yes, that is right.

Answer 18

Can we go onto the next one?

Answer 19

It's half a circle, right?

Answer 20

Find the area of the circle, then halve it.

Don't forget that the diameter is two times the radius.

Answer 21

Yes, 180 is half a circle.

Answer 22

Area of the circle is 176.71-- That divided by 2 is 88.355

Answer 23

yes, but as before, all the options are expressed in-terms of pi

Answer 24

...

What is 7.5^2 / 2?

Answer 25

28.125

Answer 26

So it would be C?

Answer 27

yeahs

Answer 28

thanks, i appreciate your help.

Answer 29

\[\ddot \smile\]