Question

What is the scale factor in the dilation?

On a coordinate plane, triangle A B C has points (4, 4), (7, 8), (10, 4). Triangle A prime B prime C prime has points (10, 10), (17, 20), (25, 10).
Two-fifths
One-half
2
2 and one-half

Answer 1

2 and one-half

Reason: A' = (10,10) is 10/4 = 2.5 times A = (4,4), and C' = (25,10) is 25/10 = 2.5 times C = (10,4), so the dilation scale factor is 2.5 (2 1/2).