Answer :
Area of a triangle is (base x height)/2
Since X and Y trisect QR, QX=XY=YR
In triangle PQX, QX is base
In triangle SRY, RY is base
Also, height of these two triangles is equal because they both are part of a same parallelogram
Since the base and height of the two triangles are equal, their areas are also equal
QED
Since X and Y trisect QR, QX=XY=YR
In triangle PQX, QX is base
In triangle SRY, RY is base
Also, height of these two triangles is equal because they both are part of a same parallelogram
Since the base and height of the two triangles are equal, their areas are also equal
QED