Problema Solution
The width of a rectangle is 2 feet shorter than it's length. If its width is decreased by 1 foot and its width is increased by 4 feet, its area would be increased by 21 feet. What is the width of the rectangle?
Answer provided by our tutors
Let
x = the length
x - 2 = the width
The area is equal to the product of length and width: x*(x-2)
If the length is decreased by 1 foot the new length will be: x - 1
If the width is increased by 4 foot the new width will be: x - 2 + 4 = x + 2
The new area is: (x - 1)(x + 2)
Since the new area increases by 21 ft^2 we can write:
(x - 1)(x + 2) = x(x - 2) + 21
........
click here to see the equation solved for x
........
x = 7.67 ft
x - 2 = 7.67 - 2 = 5.67 ft
The width of the rectangle is 5.67 feet.