Find the x-intercepts of the parabola with vertex (-3,16) and y-intercept (0,-20).
Write your answer in this form: (x1,y1),(x2,y2).
If necessary, round to the nearest hundredth.
Use the method of completing the square to write the equation of the given parabola in this form:

(y – k) = a(x – h)2

where a ≠ 0, (h,k) is the vertex, and x = h is the axis of symmetry

Question

Find the x-intercepts of the parabola with vertex (-3,16) and y-intercept (0,-20).
Write your answer in this form: (x1,y1),(x2,y2).
If necessary, round to the nearest hundredth.
Use the method of completing the square to write the equation of the given parabola in this form:

(y – k) = a(x – h)2

where a ≠ 0, (h,k) is the vertex, and x = h is the axis of symmetry

campbell_st · Answer

substitute the vertex into the equation 

$$(y - 16) = a(x + 3)^2$$

to find the value of a, substitute the y-intercept x = 0, y = -20 into the equation and solve for a. 

this will give the actual equation of the parabola... it can be re-written  as

$$y = a(x + 3)^2 + 16$$

distribute and collect like terms... 

then you will have the parabola in the standard form. 

Use the general quadratic formula to find x intercepts