Answer:
The side lengths are 10 by 7
Step-by-step explanation:
The area of a rectangle is
A = l*w
70 = (x - 11)(x - 8)
FOIL
70 = x^2 -8x-11x+88
Combine like terms
70 = x^2 -19x +88
Subtract 70 from each side
0 = x^2 -19x +88-70
0 = x^2 -19x+18
Factor
What number multiplies to 18 and adds to -19
-18*-1 =18
-18-1 = -19
0=(x-18)(x-1)
Using the zero product property
x-18=0 x-1=0
x=18 x=1
But x cannot x=1 because then the side lengths would be negative
x-18 = 10
x-11 = 7
The side lengths are 10 by 7
