Question 547972
The length of a rectangle is ten less than three times its width. If the width is increased by five and the length is increased by two, then the perimeter of the new rectangle is 90cm. Find the dimensions of the original rectangle. 
.
Let x = width
then
3x-10 = length
.
width increased by 5:
x+5
length increased by 2:
3x-10+2 = 3x-8
.
2(x+5 + 3x-8) = 90
2(4x+5-8) = 90
2(4x-3) = 90
4x-3 = 45
4x = 48
x = 14 cm (width)
.
Length:
3x-10 = 3(14)-10 = 42-10 = 32 cm
.
Dimensions:
14 cm by 32 cm