The width of a rectangle is h - 4 and the length is 3h + 5. Which is equal to the area of a rectangle?

3h^2 - 20

3h^2 - 17h + 20

3h^2 - 7h - 20

4h^2 - 17h - 20

Question

The width of a rectangle is h - 4 and the length is 3h + 5. Which is equal to the area of a rectangle?

3h^2 - 20

3h^2 - 17h + 20

3h^2 - 7h - 20

4h^2 - 17h - 20

anonymous · Answer

I know I have to multiply the length and width to find the area. (h-4)(3h+5) And I have to us the FOIL method but then I get confused.

anonymous · Answer

First: h x 3h= 3h^2
Outer: h x 5=5h
Inner: -4 x 3h= -12h
Last: -4 x 5= -20

3h^2 + 5h - 12h - 20

Then I combine like terms: 5h + -12h= -7h. And I get...

3h^2 - 7h - 20

Nevermind...I guess I worked it out myself. :) I just kept getting the answer wrong the first few times I worked it out.