the sum of squares of the adjacent sides = hypotenuse^2
leg1^2+leg2^2=hypotenuse^2
In a right triangle the largest side is aways the hypotenuse.
First the basic one
3,4,5
3^2+4^2=5^2
(+16=25
25=25
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5,12,13
5^2+12^2=13^2
25+144=169
169=169
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Third one you can find