## anonymous one year ago What is the area of the rectangle? Round to the nearest square inch. A. 27 in2 B. 31 in2 C. 45 in2 D. 47 in2 http://static.k12.com/calms_media/media/1579000_1579500/1579373/2/4ac8cba629d8de89098f07b616577fd1aa6b2747/MS_IMC-150126-130912.jpg

1. iGreen

Use the Pythagorean Theorem to find the Length of the rectangle.

2. iGreen

$$\sf a^2 + b^2 = c^2$$ 'a' and 'b' are the two legs, in this case the length and the width, and 'c' is the hypotenuse, in this case the diagonal of the rectangle.

3. anonymous

so its $5^2+b^2=8^2$ ??

4. iGreen

Yep, you got it.

5. iGreen

Now solve for 'b'

6. anonymous

how do i solve for b again?

7. iGreen

Then after you find 'b', multiply it to 5 to get the Area.

8. iGreen

$$\sf 5^2 + b^2 = 8^2$$ Subtract 5^2 to both sides: $$\sf b^2 = 8^2-5^2$$ Find the square root of both sides: $$\sf b = \sqrt{8^2-5^2}$$

9. iGreen

Simplify

10. anonymous

i got $b=\sqrt{39}$

11. iGreen

Yep, now find the square root of 39

12. anonymous

6.24

13. iGreen

Yep, now multiply it to 5.

14. anonymous

31.2 or 31

15. iGreen