(05.05)polygon abcd has the following vertices: a(−5, 4), b(1, 4), c(6, −4), and d(−5, −4) calculate the area of the polygon.

The first thing you should do is draw the points in the Cartesian plane and then join them to find the polygon.
 The searched polygon can be seen in the attached image.
 The area of the polygon will be the area of the square plus the area of the triangle.
 At = (6) * (8) + (1/2) * (5) * (8) = 68
 At = 68
 answer
 the area of the polygon is 68units ^ 2

Then just do it (lol)