Find the area of the polygon defined by the coordinates (0, -5), (-5, 0), (-15, -20), and (-20, -15).

Answer 1

By using trig the points from the short sides for the triangle sas=5,90,5.The difference between -15 and -20 is 5. Same for the second side. The formula is a^2+b^2=c^2. So 25+25=50^.5=7.071

Same for the long side. Difference between -20 and -5 is 15; and between 15 and 0 is 15.

Using the 2 differences we get 15^2+15^2=450^.5=21.213.

Area=7.071*21.213=150

Answer 2

This polygon is a rectangle.

Using the Pythagorean Theorem, the sides are:

5√2

15√2

The area is: A = bh

A = (15√2) * (5√2)

A = 15*5*2

A = 150 square units