Final answer:
The given side lengths can form one triangle.
Step-by-step explanation:
To determine the number of triangles that can be formed with given side lengths, we need to apply the triangle inequality theorem. According to the theorem, the sum of the lengths of any two sides of a triangle must be greater than the length of the third side. Let's check if the given side lengths satisfy this condition:
3 in. + 2.9 in. > 5 in. (True)
3 in. + 5 in. > 2.9 in. (True)
2.9 in. + 5 in. > 3 in. (True)
Since all three inequalities are true, the given side lengths can form a triangle. Therefore, there is exactly one triangle that can be formed.
Learn more about Triangle inequality theorem