In the diagram, square ABCD has side length 3. Find the area of triangle PDQ.
angle ABP + angle BPA = 90
angle DPQ + angleBPA = 90
So
angle ABP = angle DPQ
tan ABP = 1/3
So tan DPQ = 1/3
1/3 = DQ/2
DQ = (2/3)
[ PDQ ] = (1/2) PD * DQ = (1/2) (2) (2/3) = 2/3
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