algebra
posted by Anonymous .
A triangle has an area of 20 inches squared. Every dimension of the triangle is multiplied by a scale factor, and the new triangle has an area of 180 inches squared. What is the scale factor.

if a rectangle (or any 2dimensional figure) is scaled by a factor of n, then
length l becomes nl
width w becomes nw
area lw becomes (nl)(nw) = n^2(lw) = n^2 times the old area
For your rectangle, the new area is 9 times the old area, so the scale factor is √9 = 3 
a triangle has an area of 20 inches squared. every dimension of the triangle is multiplied by a scale factor, and the new triangle has an area of 180 inches squared. what was the scale factor?

9