Question

Write a simplified polynomial expression to represent the area of the rectangle below.

Answer 1

To do this, we need to know that the area of the rectangle is A=b*h.
We see that the base, b= 2x-4, and the height, h = x+5
Then A=(2x-4)*(x+5)

To simplify, we need to multiply this out, and we are going to FOIL.
FIRST: 2x*x
OUTSIDE: 2x*5
INSIDE: -4*x
LAST: -4*5

FOIL: 2x^2 +10x -4x -20
Combine "like terms"
2x^2+6x-20=A

HTH!