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Algebra problem (42) |  |
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Problem
Pictured below are squares.The red surface is 20.
How big is the blue surface?
Solution
Say EF=EC=a and BC=CK=b
The red surface is (a+b)2 + (a-b)2 = 2(a2+b2)
The blue surface is a2 + b2.
The blue area is half the red area so 20/2 = 10.
