does a triangle with sides 6, 8, 10 have to be a right triangle(or can it be obtuse or acute)?

Guest Jul 18, 2017

#1**+1 **

This is the well known example of the 3-4-5 right angled triangle (each side is just twice 3, 4 and 5 respectively). So, yes, it must be a right angled triangle.

You can check using Pythagoras theorem: 6^2 + 8^2 → 36 + 64 → 100 and 10^2 → 100

i.e. The square on the hypotenuse is equal to the sum of the squares on the two adjacent sides (only true for right angled triangles).

Alan Jul 18, 2017