How do you use the pythagorean theorem to solve a=x-5 b=x 2 c=13?

1 Answer
Apr 22, 2016

So acceptable value of x is 10

Explanation:

Here sides are
a=x-5
b=x+2
c=13
Taking c as larger side i.e. hypotenuse
we can apply Pythagorean theorem

a^2+b^2=c^2
=>(x-5)^2+(x+2)^2=13^2
=>(x^2-10x+25+x^2+4x+4)=169
=>(2x^2-6x-140)=0
=>x^2-3x-70=0
=>x^2-10x+7x-70=0
=>x(x-10)+7(x-10)=0
=>(x-10)(x+7)=0
So acceptable value of x is 10
otherwise a and b will be negative for x = -7