Answer:
36
Explanation:
since the triangles are similar, that means that they have the same angles, and all 3 correlating sides have the same scaling factor.
C correlates to R.
B to Q.
A to P.
therefore,
CB correlates to RQ.
84 / 18 = 14 / 3
so, the scaling factor from ABC to PQR is
3/14
AB to PQ must have the same scaling factor :
168 × 3/14 = 12 × 3 = 36
which is also (of course) confirming the ratio of leg to baseline of the original triangle :
AB : CB = 168 : 84 = 2 : 1
and now
PQ : RQ = 36 : 18 = 2 : 1