Answer :
Answer:
length of a rectangle = l = 7 in
Step-by-step explanation:
Let,
width of a rectangle = w
length of a rectangle = l
Area = A = 77 in
A = w×l ------> (equation 1)
According to given condition:
w = l + 4 put in (equation 1)
equation 1 ⇒ A = (l + 4)×l
77 = (l + 4)×l
77 = l² + 4l
l² + 4l -77 = 0
l² + 11l - 7l -77 = 0
(l² + 11l) - (7l + 77) = 0
l(l + 11) - 7(l + 11) = 0
(l + 11) (l - 7) = 0
(l + 11) = 0 or (l - 7) =0
l = -11 or l =7
as length is always positive, therefore
length of a rectangle = l = 7 in
w = l + 4
w = 7 + 4
width of a rectangle = w = 11 in