You can check whether this is true using Pythagoras' Theorem. The Pythagorean Theorem:
a² + b² = c², where c is the hypotenuse of a right triangle.
Let's plug in the given values and check the validity of the statement.
a² + b² = c²
7² + 9² = 11²
49 + 81 = 121
130 = 121
This is false. Thus,
Answer:
False - a triangle with side lengths 7, 9, and 11 is not a right triangle.