Question

A triangle has sides of lengths 9, 7, and 12. Is it a right triangle? Explain.

Answer 1

No,
`9^2 +7^2 \\eq 12^2`

Explanation:

`9^2 +7^2 = 81+ 49 =130...(1)`

`12^2 = 144...(2)`

From equations (1) & (2) it is obvious that:

`9^2 +7^2 \\eq 12^2`

Thus, the given is not a right triangle.