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Answer:
D. 12
Step-by-step explanation:
There are a number of ways to find the area of this rectangle. Perhaps the most straightforward is to find the lengths of the sides and multiply those. The distance formula is useful.
d = √((x2 -x1)^2 +(y2 -y1)^2)
Using the two upper-left points, we find the length of that side to be ...
d = √((3 -0)^2 +(3 -0)^2) = √(9 +9) = √18 = 3√2
Similarly, the length of the lower-left side is ...
d = √((-2 -0)^2 +(-2 -0)^2) = √(4+4) = √8 = 2√2
Then the area of the rectangle is ...
A = LW
A = (3√2)(2√2) = 3·2·(√2)^2 = 3·2·2 = 12
The area of rectangle ABCD is 12.
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Other methods include subtracting the area of the corner triangles from the area of the bounding square:
5^2 -2(1/2)(3·3) -2(1/2)(2·2) = 25 -9 -4 = 12
