The figure above shows three consecutive squares of sides 5, 4 and 3, respectively.
Find the area of the black region.
Hello Guest!
\(A=5^2+4^2+3^2-\frac{(5+4+3)\cdot5}{2}\\ A=25+16+9+30\\\)
\(A=80\)
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Nope, it cannot be 80!!!
A = ( 52 + 42 + 32 ) - 1/2 ( 5 * 12 ) = 20
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