The lengths of two sides of a right triangle are 12 inches and 15 inches. what is the difference between the two possible lengths of the third side of the triangle? round your answer to the nearest tenth.

The problem is using a right triangle, it means we can use the Pythagorean theorem in solving the problem. We have two possible measurements for the third side.
First length, when the third side is the hypotenuse:
x ² = 15² + 12²
x = 19.21

Second possible length, when the third leg is either an adjacent or base side:
15² = x² + 12² 
x = 9

Therefore, the difference between the two possible answers are shown below:
Difference = 19.21 - 9 = 10.21