Question

How do you use coordinates to find the perimeter and area of polygons?

Answer 1

\[A = \frac{ 1 }{ 2 }|(x_1 \times y_2 - x_2 \times y_1)+(x_2 \times y_3 - x_3 \times y_2) + (x_3 \times y_1 - x_1 \times y_3)|\]

Answer 2

Assuming it's a 3 sided polygon.

Answer 3

As for perimeter you just find the length of each side using the distance formula:
\[d=\sqrt{(x_1-x_2)^2+(y_1-y_2)^2}\]