The shorter leg of a right triangle is 6 m shorter than the longer leg. The hypotenuse is 6 m longer than the longer leg. What are the side lengths of the triangle?

1 Answer
Mar 5, 2017

Length of the longer side = #24m#
Length of the shorter side = #18m#
Length of the hypotenuse = #30m#

Explanation:

From the data given, we can write:

Length of the longer side = #x#
Length of the shorter side = #x-6#
Length of the hypotenuse = #x+6#

The Pythagorean Theorem states the the square of the hypotenuse is equal to the sum of the squares of the other two sides. Hence.

#x^2+(x-6)^2=(x+6)^2#

#x^2+x^2-12x+36=x^2+12x+36#

Cancel equivalent terms on each side.

#x^2+cancelx^2-12x+cancel36=cancelx^2+12x+cancel36#

#x^2-12x=12x#

Subtract #12x# from each side.

#x^2-24x=0#

Factorise.

#x(x-24)=0#

#x=0# or #x-24=0#

#x=0# or #x=24#

Since the length has to be a positive integer, the length of the longer side is #24m#.

Hence:
Length of the longer side = #24m#
Length of the shorter side = #18m#
Length of the hypotenuse = #30m#

To verify, we apply the Pythagorean Theorem:

#24^2+18^2=30^2#

#576+324=900#

Since the two sides are equal, the calculations have been verified.