Triangle XY Z is similar to triangle PQR
Solve for k.
k=
19.5
10.5
R
5.5
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We can write a proportion between short and long legs:
[tex]10.5\div k = 16.5\div 5.5[/tex]
Solving for k yields
[tex]k = \dfrac{10.5\cdot 5.5}{16.5}=3.5[/tex]