Question 781985
{{{Perimeter=(x+9)+(x+2)+(x+10)}}}
Using Pythagorean theorem
{{{(x+9)^2+(x+2)^2=(x+10)^2}}}
Expanding
{{{(x^2+18x+81)+(x^2+4x+4)=(x^2+20x+100)}}}
simplified
{{{x^2+2x-15=0}}}
using quadratic formula
{{{x= -5}}}{{{or }}}{{{x=3}}}
If x is -5 than the base would be -3 and you can't have a negative distance...
So {{{x=3}}}