First we need to see the pythagorean formula which is
[tex] a^2 + b^2 = c^2 [/tex]
Substituting the given values of a,b , we will get
[tex] (x^2 -1)^2 + (2x)^2 [/tex]
[tex] = x^4 +1 -2x^2 +4x^2 [/tex]
[tex] = x^4 +1 +2x^2 [/tex]
[tex] = (x^2 +1)^2 [/tex]
And
[tex] (x^2 +1)^2 = c^2 [/tex]
So we have
[tex] a^2 + b ^2 = c^2 [/tex]
So the given triangle is a right triangle .
