Which equation has solutions of 6 and - 6

I don't see any answers provided so, i'm going to add, subtract, multiply, and divide with 6 and - 6.

6 + - 6 = 0 | Another solution: Any number multiplied by 0

6 - (-6) = 12 | Another Solution: 6 + 6

6 · - 6 = - 36 | Another Solution: - 6 squared

6 / - 6 = - 1 | Another Solution: - 1 x 1

x2 - 36 = 0