Answer:
9 u^2
Explanation:
there's 2 ways to solve this problem
easy way
plot every coordinate and youll see it's a square
square area = side^2
3^2 = 9 answer
and this method
working with 3 points (triangle)
W - X - Y
0 0
0 3
-3 3
0 0
--------------
2
--------------------------------------
0 0
0 -9
0 0
-----------
l-9/2l
4.5
since a square is made of 2 triangles
4.5 * 2 = 9 u^2