You do not square the area. You square the scale factor.
area scales by the square of the linear scale factor, since
a = 1/2 bh
if everything is scaled by 3, that gives you
1/2 (3b)(3h) = 1/2 * 9bh = 9(1/2 bh) = 9a = 9*13 = 117 m^2
A right triangle has an area of 13 m^2. The dimensions of the triangle are increased by a scale factor of 3. What is the area of the new triangle?
A) 39 m^2
B) 169 m^2
C) 117 m^2
D) 142 m^2
I think it is B
1 answer