Question

Name:

Answer 1

Answer:

length is 10, width is 7

Step-by-step explanation:

Area of a rectangle = length * width = lw

Area is known to be 70

length = twice width - 4 = 2w-4 = l

width=w

so A = lw = (2w-4)w = 70

(2w-4)w=70

2w^2-4w=70

2w^2-4w-70=0, divide by 2

w^2 - 2w - 35 = 0, not sure how your class solves these, I see visually

(w-7)(w+5)=0

w=7 or w=-5, -5 makes no sense in the real world (negative length), so w=7

l = 2w-4 = 2(7)-4 = 14-4 = 10