Answer:
length=16 inches
width= 5 inches
Step-by-step explanation:
Area=l*w=80 square inches
l*w=80 (equation 1)
l=4w-4 (equation 2)
Putting value of l from equation 2 in equation 1
(4w-4)w=80
4w^2-4w-80=0 (equation 3)
Taking 4 common from equation
4(w^2-w-20)=0
w^2-w-20=0
w^2-5w+4w-20=0
w(w-5)+4(w-5)=0
(w+4)(w-5)=0
w=-4, w=5
ignoring the negtive width
we'll solve with w=5 by putting it in equation 2
l=(4*5)-4
l=20-4
l=16
