In a right triangle defined by the Pythagorean theorem, the side lengths \( a \) and \( b \) are the legs, and \( c \) is the hypotenuse. In the Pythagorean triple (9, 12, 15), the two legs of the triangle are 9 and 12, and the hypotenuse is 15.
Since you are asked for the value of \( a \), it can represent either of the legs (9 or 12), but traditionally, the smaller leg is often referred to as \( a \).
Given your options, the correct value of \( a \) could be:
- \( a = 9 \)
- \( a = 12 \)
If we assume \( a \) represents the smaller leg, then:
Correct answer: a = 9