Problema Solution
A rectangle has length 3x and width x+1. For what values of x is the perimeter of the rectangle between 50 and 90 feet? Write your answer in set notation.
Answer provided by our tutors
the perimeter of the rectanle = 2(length + width)
50 < 2(length + width) < 90 divide both sides by 2
25 < length +width < 45
25 < 3x + x + 1 < 45
25 < 4x + 1 < 45
24 < 4x < 44 divide both sides by 4
6 < x < 11
x is element of the set {x | x is a real number and 6 < x < 11} is the answer.