Answer:
ΔABC ~ ΔPQR
Explanation:
In similar triangles, corresponding sides are always in the same ratio.
Therefore, if triangle ABC is similar to triangle PQR then:

Substitute the side lengths into the ratio equation:


Simplify each ratio by dividing all parts of the ratio by their highest common factor:


As the corresponding sides of triangles ABC and PQR are in the same ratio, this proves that the two triangles are similar.