find the x-intercepts of the parabola with vertex (-3,16) and y-intercept (0,-20). write in the form of (x1,y1), (x2,y2) and round to the nearest hundredth.
I don't see that there's anything to round here. I used the basic formula of a vertex form parabola: y = a(x-h)^2 + k and the information they gave us and solved for a. Like this: -20 = a(0+3)^2 + 16; -20 = 9a + 16; -36= 9a; a = -4. Now fill in to find the actual equation of this thing so you can factor it and find the zeros. y = -4(x+3)^2 + 16 simplifies to y = -4(x^2 + 6x + 5). When you're finding the x-intercepts it's important to remember that the x-intercepts exists when y = 0. So to find the x-intercepts, we will set the equation equal to 0 and solve for x by factoring. 0 = -4(x+1)(x+5) which gives us x = -1 and -5. Written in the form you want it in (coordinate form) is (-1, 0) and (-5, 0)
