Answer:
PQ=36
Step-by-step explanation:
If the triangles are similar, then they must have a common ratio between them.
RQ corresponds with CB, so [tex]\frac{84}{18}=\frac{14}{3}[/tex]
If the ratio is [tex]\frac{14}{3}[/tex], then [tex]\frac{168}{\frac{14}{3}}=36[/tex], so PQ=36.
