Question 128873
The length of an equal side is x, so the length of the base is x - 3.  The perimeter is the sum of the lengths of the sides, so:


{{{x + x + (x -3)= 36}}}


{{{3x-3=36}}}


{{{3x=39}}}


{{{x=13}}}


The equal sides are 13 cm and the base is 10 cm.