SOLUTION: The length of a rectangle is 15 cm longer than the width. when its width is increased by 3 cm and its length decreased by 5 cm. the area of the new rectangle is 20cm2 bigger than t

Algebra ->  Rectangles -> SOLUTION: The length of a rectangle is 15 cm longer than the width. when its width is increased by 3 cm and its length decreased by 5 cm. the area of the new rectangle is 20cm2 bigger than t      Log On


   



Question 465604: The length of a rectangle is 15 cm longer than the width. when its width is increased by 3 cm and its length decreased by 5 cm. the area of the new rectangle is 20cm2 bigger than the original. find the original dimension of the rectangle.
Answer by amoresroy(361) About Me  (Show Source):
You can put this solution on YOUR website!
Let x = width of the rectangle
x + 15= the length of the rectangle
(x+3)(x+15-5) = x(x+15) + 20
x^2+10x+3x+30 = x^2+15x+20
30-20 = 15x-10x-3x
2x = 10
x = 5
x+15 = 5+15 = 20
The dimension of original rectangle are:
width = 5 cm.
length = 20 cm.