Answer:
The option that best describes a triangle with side lengths of 6 inches 8 inches and 9 inches is:
C) a unique , acute triangle
Explanation:
We know that with the help of given three side lengths always a unique triangle is possible.
Pythagorean Theorem for acute angles states that:
If c is the longest side of a triangle and a and b are other two sides of a triangle.
Then,

Here the three sides of a triangle are:
6 inches 8 inches and 9 inches.
i.e. the longest side i.e. c = 9 inches.
Also, let a=6 inches and b=8 inches.
and

Hence, the triangle is a acute triangle.