To determine the zeroes of the factored quadratic equation, we need to look back at its definition. The zeroes are a function are specific x-values that result in a y-value of 0.
In this case, we want the numbers inside of the parantheses to equal 0. If we substitute in x = -3, we get (0)(x - 1), and we know that is just 0. Similarly, if we substitute in x = 1, we get (x + 3)(0), and we know that is just 0.
