Answer:
width = 5 feet
length = 11 feet
Explanation:
Using one variable and setting up two expressions equal to the total area of the rectangle will determine the dimensions of the rectangle.
w = width
l = '4 feet less than three times the width' or 3w - 4
Area = length x width
A = w(3w - 4) = 55
Distribute: 3w² - 4w = 55
Set equation equal to '0': 3w² - 4w - 55 = 0
Multiply 3 x -55 = -165 and find two factors with a product of -165 and sum of -4: -15 and 11.
3w² - 15w + 11w - 55
Group and find the GCF (greatest common factor):
3w(w - 5) + 11(w - 5)
(3w + 11)(w - 5) = 0
3w + 11 = 0 and w - 5 = 0
w = -11/3 not possible to have negative measurement
w = 5 feet
Solve for length: 3(5) - 4 = 11 feet