Question 92365
Let the 2 equal sides measure x cm

Then by Pythagorean theorem, 

x^2 + x^2 = 82 ^2

==> 2x^2 = 6724
==> x^2 = 6724/2

        = 3362

==> x = sqrt (3362) 

      = 57.98 cm

So each equal side measures 57.98 cm