What is the length of side PQ?

Answer: The length of PQ = 64
Step-by-step explanation:
We are given that ΔPQR and ΔABC are similar right triangles .
Since, we know that the corresponding sides of similar triangles are proportional.
Therefore, we get
[tex]\dfrac{PQ}{AB}=\dfrac{QR}{BC}\\\\\Rightarrow\dfrac{PQ}{16}=\dfrac{80}{20}\\\\\Rightarrow\ PQ=4\times16\\\\\Rightarrow\ PQ=64[/tex]
Hence, the length of side PQ = 64 units