Find the x-intercept(s) and the coordinates of the vertex for the parabola =y−x2−2x3. If there is more than one x-intercept, separate them with commas.

Step-by-step explanation:

Your equation makes no sense.

I will ASSUME you mean

y = -x² - 2x + 3

which can be factored

y = (x + 3)(-x + 1)

x intercepts occur when y = 0

0 = (x + 3)(-x + 1)

which means either

x + 3 = 0

x = -3

or

-x + 1 = 0

x = 1

x intercepts are (-3, 0) and (1, 0)

The vertex will occur halfway between these point

x = (-3 + 1) / 2 = -1

so vertex = y = -(-1)² - 2(-1) + 3 = 4

(-1, 4)