The perimeter of a rectangle is the sum of all four sides of the rectangle.
(Perimeter = 2width + 2length)
Let's assume the width of the rectangle to be x.
For length, the statement says that is equals to 3 times the width (= 3x) and 5cm more meaning 5cm would be added to 3 times the width.
Width = x
Length = 3x + 5
Perimeter = 2x + 2(3x+5)
74 = 2x + (6x+10)
74 = 8x + 10
solve for x
8x = 74 - 10
x = 64/8, x=8
Width = 8
length = 3(8)+5 = 29
