Question

What is the scale factor from ABC to DEF?

Answer 1

Within similar triangles, the angles are the same. So, we need to look at the side lengths then.

72 to 12

66 to 11

42 to 7

In each pair of corresponding side lengths, the original side length from triangle ABC is divided by 6 (or multiplied by 1/6) to get the smaller side length on triangle DEF.

The scale factor from ABC to DEF is 1/6.

Hope this helps!