Lukas wants to create a triangle with sides measuring 9 in., 13 in., and 15 in. He says that more than one triangle is possible given these side lengths. Which statement about Lukas’s claim is true?

For side lengths 9, 13, and 15, the sum of the two shorter sides is 9 + 13 = 22, which is greater than 15, so the triangle inequality is satisfied. Three fixed side lengths determine one unique triangle (up to flipping or rotating it), not multiple different triangles. Therefore, Lukas is incorrect, as stated in choice A.

AI-written and checked against the verified answer.