If the diagonal of a rectangle is 19 cm long and its perimeter is 50 cm. Find the area of the rectangle in sq cm.

Answer 1

132 sq cm

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If sides of the rectange are a and b, then we have:
2*(a+b)=50
a^2+b^2=19^2
a*b=?

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a+b=25 ---> (1)
a^2+b^2=19^2 ---> (2)
(1)^2-(2)= 2a*b => a*b=(25^2-19^2)/2=132 sq cm.