SOLUTION: The sum of the lengths of the two legs of a right triangle is 21 inches. If the length of the hypotenuse is 15 inches, find the length of the legs.

Algebra ->  Triangles -> SOLUTION: The sum of the lengths of the two legs of a right triangle is 21 inches. If the length of the hypotenuse is 15 inches, find the length of the legs.      Log On


   

Question 366879: The sum of the lengths of the two legs of a right triangle is 21 inches. If the length of the hypotenuse is 15 inches, find the length of the legs.
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi, 

Let x represent the length of one of the legs, then (21-x) would be the other leg

Applying the Pythagorean Theorem

x^2 + (21-x)^2 = 15^2

x^2 + 441 - 42x + x^2 = 225

2x^2 -42x + 216 = 0

x^2 -21x + 108 = 0

(x-12)(x-9) = 0

x= 12

x= 9



legs are 9in and 12in  (21in - 9in)