The dashed triangle is the image of the solid triangle for a dilation with center at the origin. What is the scale factor?

Question

The dashed triangle is the image of the solid triangle for a dilation with center at the origin. What is the scale factor?

the link of the image : drive.google.com/file/d/1uu5-rKuSc2N7oA6PrieawnOiHDsr1oJM/view?usp=sharing

Answer 1

The scale factor k is the ratio of the lengths of corresponding sides. So compute the lengths of two corresponding sides and take the ratio of the longer side over the shorter side.

k = (Length of side on bigger triangle) / (Length of corresponding side on smaller triangle)

The easiest sides to use would the two horizontal bases because you just need to count ticks on the graph to figure out their lengths. If you use other sides you'll need to use the distance formula.