ABCis a trangle, D is midpoint of AB, p is any point on BC. Line CQ is parallel toPD to intersect AB at Q. PQ is joined.
pt ar(bpq) = 1/2 ar(abc)

Here is the solution to your question-

D is the midpoint of the side BC.

Thus, in triangle ABC, CD is the median of the side AB.

Thus,

......(1)

Since triangles PDQ and PDC are on the same base PD and between the parallel lines PD and QC.

Consider equation (1).

Thus it has been proved that