The hypotenuse of a right triangle is 13ft long. The shorter leg is 7ft shorter than the longer leg. Find the side lengths of the triangle.

Mathematics · College · Wed Jan 13 2021

Answered on

Given:

Hypotenuse = 13 ft 

Shorter leg is 7ft shorter than the longer leg,

So, let the shorter leg be x ft

Then, longer leg is x + 7 ft

By phythogoras theorem

H² = B² + P²

13² = x² + (x +7)²

169 = x² + x² + 14x + 49

2x² + 14x + 49 - 169 = 0

2x² + 14x -120 = 0

Or, x² + 7x - 60 = 0

By middle-term split method 

x² + 12x - 5x - 60  =0

x(x + 12) - 5(x +12) = 0

(x + 12) (x -5)  =0

Let x + 12 = 0

x = -12

Length cannot be in negative

x - 5 = 0

x = 5

So, shorter leg = 5 ft

Longer leg = 5 + 7 = 12 ft