Question

Polygon ABCD has the following vertices: A(−3, 3), B(5, 5), C(5, −4), and D(−3, −4) Calculate the area of the polygon.

Answer 1

check the picture below.

notice, is really just an 8x7 rectangle, with a triangle on top, the triangle has a base of 8, and a height of 2.

so, just get the area of the rectangle and the triangle, recall that A = 1/2 bh for a triangle, and sum them up, and that is the area of the polygon.