Find the area of a triangle ABC when c=15m, a=20 m, and b=10 m (this problem is an area of triangles using trig)

If anyone has done the algebra 2 chaos theory portfolio would you be wiling to me? i kind of know what i'm doing i just don't know if i'm doing it right.

Given: pqrs is a parallelogram prove: pr and qs bisect each other at t

How are algebraic expressions evaluated using substitution?