Answer:
Yes, it is a right triangle.
Explanation:
a^2+b^2=c^2
The longest side is the hypotenuse so c^2 would be 90.
72^2+54^2=90^2
72 and 54 can be either a or b.
Solve for all exponents: 5184+2916=8100.
That equation is true, so the triangle is a right triangle.