Polynomials can have double roots, in fact they're pretty common. if you get a reasonable zero it costs very little time to try it again for a double root. answer is the second choice
Inverse operations are operations that undo each other. In this case, 10 + 2 = 12, and 12 - 2 = 10 A multiplication example could be 4 x 2 = 8, and 8 ÷ 2 = 4
