So before we can find the perimeter, we need to find the hypotenuse. Since this is a right triangle, we can use the pythagorean theorem. The equation for that is [tex] a^2+b^2=c^2 [/tex] , in which a and b are the legs of the triangle and c is the hypotenuse.
With this info, we can form our equation: [tex] 9^2+12^2=c^2 [/tex]
Firstly, solve the exponents: [tex] 81+144=c^2 [/tex]
Next, combine everything on the left side: [tex] 225=c^2 [/tex]
Next, square root both sides, and your hypotenuse will be 15 = c.
Now that we have all the triangle side lengths, just add everything up: [tex] P=9+12+15=36 [/tex]
In short, the perimeter is 36 inches.
