Please answer, right answer = brainliest.

Answer:
no
Step-by-step explanation:
to find out whether a triangle is a right triangle we can use the pythagorean theorem
a²+b²=c²
a= one side of the triangle
b= one side of the triangle
c= the hypotenuse (or biggest side )
21^2+ 72^2= 76^2
441+ 5184= 5776
5625 = 5776 X
since the sums do not equal this means that it is not a right triangle.
i hope this helps!!