Find the area of quadrilateral whose verties are A(0,2), B(2,7), C(6,10), and D (9,-2).

2 answers

There is an old method, called Pick's theorem: https://en.wikipedia.org/wiki/Pick%27s_theorem

So graph the points on graph paper, count the points, and use the formula.
(AB)^2 = (2-0)^2 + (7-2)^2 = 29,
AB = 5.39.

(BC)^2 = (6-2)^2 + (10-7)^2 = 25,
BC = 5.

(CD)^2 = (9-6)^2 + -2-6)^2 = 73,
CD = 8.54.

(AD)^2 = ((9-0)^2 + (-2-2)^2 =
AD =

P = AB + BC + CD + AD =

A^2 = (P*AB*BC*CD*AD)/16 =
A =