x- intercepts are intersection points of the parabola f(x) with the x-axis, where f(x) = 0, or, which is the same,= 0. So, you need to solve the equation = 0. It is equivalent to = 16. Take the square root from both sides. You will get x + 2 = +/- 4. So, there are two options and two solutions. They are 1) x + 2 = 4 ====> x = 4 - 2 = 2. 2) x + 2 = -4 ====> x = -4 - 2 = -6. Answer. There are two solutions: x= 2 and x= -6.