in a rectangle ABCD ,P is midpoint of seg.AB. S & T are points of trisection of seg. DC . if area of the rectangle is 70 sq.units. & a triangle is drawn ie.triangle PST and a diagonal bd of rectangle cuts this triangle in points R and Q (B-R-Q-D). then find the area of triangle PQR.(PLZZ XPLAIN)

eqn of line Ab is : x/a y/b =1

also area of rectangle ABCD=ab= 70 sq. units

eqn of line MP = y= -6b/a*(x-a/2)

eqn of line NP = y= 6b/a*(x-a/2)

on solving above line we get P(a/2,0) Q,R as shown in figure

now from 3 vertices, we can simply find area and substitute 79 sq. units for area ab

whihc comes to be 3 sq. units

--

regards

Ramesh