Corresponding sides in the triangles MOP and MNQ are
MO and MN,
OP and NQ,
PM and QM.
Ratios of the corresponding sides for similar triangles should be the same.
MQ/MP =MN/MO
MQ/(MQ+QP) = MN/(MN+NO)
5/(5+x) = 6/(6+18/5)
5*(6+18/5)=6(5+x)
30+18 = 30 +6x
18=6x
x=3 =QP
