<PRE><B>Question 644277</B>
How do you find the area of a diamond figure?
The coordinates I have are the following:
Q (-1,-5) U (4,5)
A (0,2) D (4,0)
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Q...A...U...D...Q
-1 +0 +4 +4 -1
-5 +2 +5 +0 -5
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Add the diagonal products starting at the upper left
-1*2 + 0 + 0 - 4*-5 = -2 - 20 = -22
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Add the diagonal products starting at the lower left
0 + 2*4 + 5*4  0 = 28
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ABS of the difference = 50
Area = 50/2 = 25 sq units
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