The polynomial function has roots. The first root is 3 and the second is √7.
When we have a square root that means that we get two roots from the same number but one is negative and the other is positive. For example, if we have:
√x² = ±x
Because we can have:
(-x)² = x², or
(x)²=x².
So a square root always gives us two answers, one negative and the other positive.
