geometry
posted by Kalem on .
A rectangle measures 6 inches in length by 9 inches in width. If the rectangle will be enlarged by 250%, what will be the lengths of the sides of the new rectangle?
What percent bigger is the perimeter of the new rectangle, compared to the original?

original area = 54 in^2
new area = 54(2.5) = 135 in^2
Assuming the new rectangle is similar to old one,
length = 9x , width = 6x
54x^2 = 135
x^2 = 2.5
x = √2.5 = 1.58
new length = 9(1.58) = appr. 14.23 in
new width = 6(1.58) = 9.49 in
percentage increase of perimeter = 58%
new perimeter is 158 % of old one