Question 281253
{{{a^2 + b^2 = c^2}}}
{{{9^2 + b^2 = 15^2}}}
{{{81 + b^2 = 225}}}
{{{b^2 = 144}}}
{{{b=12}}}
9,12,15 is in the ration 3,4,5 whicah are always right triangles

{{{sqrt(625) = 25 or -25}}}
principle sqrt = 25 (the positive one)