The triangle STV is not a right angled triangle.
Explanation:
Given that STV is a triangle with side lengths of 7, 11 and 14 units
We need to determine that STV is a right angled triangle.
Using Pythagorean theorem, we have,

where
and 
Substituting the values in the above formula, we have,

Squaring the terms, we get,


Since, both sides of the equation are not equal, then the triangle STV is not a right angled triangle.