Question 186758
The longest side is the hypotenuse. So  by Pythagorean Theorem, 15^2 = 9^2 + x^2
where x is the unknown side

x^2  = 15^2 - 9^2  = 225 - 81 = 144
so x  = sqrt(144) = 12 cms

The perimeter = sum of the length of all 3 sides = 12+15+9 = 36 cms

Area = 1/2 base x height = 1/2 x 12 x 9 = 54 sq cms



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