Answer:
w = 31
L = 70
Explanation:
Givens
L = 2*w + 8
w = w
Area = 2170
Equation
Area = L*w
Solution
Area= w * (2w + 8) = 2170 Remove the brackets
2w^2 + 8w = 2170 Divide each term by 2
w^2 + 4w = 1085 Subtract 1085 from both sides.
w^2 + 4w - 1085 =0 Factor
(w - 31)(w + 35) = 0
w + 35 doesn't yield anything.
w - 31 = 0 Add 31 to both sides.
w = 31
L = 2*w + 8
L = 2*31 + 8
L = 70