Hey there! :)
Answer:
These two figures are similar because 5/3 equals 15/9.
Explanation:
These figures are similar to each other, which means the side-lengths are proportional. Therefore:
![(5)/(9) = (15)/(9)](https://img.qammunity.org/2021/formulas/mathematics/high-school/s8h2tnj1exygy23c6r70ig4soxwdkexie0.png)
Side-lengths 15 and 9 are proportional to 5 and 3 because the two fractions are equivalent; the larger rectangle is just 3 times larger.