Example

Finding the Intercepts of y=x212x36y = -x^2 - 12x - 36

To find the intercepts of the parabola y=x212x36y = -x^2 - 12x - 36:

Finding the y-intercept: Substitute x=0x = 0 into the equation and compute yy:

y=(0)212(0)36y = -(0)^2 - 12(0) - 36 y=36y = -36

The y-intercept is the point (0,36)(0, -36).

Finding the x-intercepts: Substitute y=0y = 0 into the equation and solve for xx:

0=x212x360 = -x^2 - 12x - 36

Factor out 1-1 to simplify the quadratic expression:

0=(x2+12x+36)0 = -(x^2 + 12x + 36)

Recognize and factor the perfect square trinomial:

0=(x+6)20 = -(x + 6)^2

Apply the Zero Product Property:

x+6=0x + 6 = 0 x=6x = -6

Since there is only one real solution, the parabola has exactly one x-intercept at the point (6,0)(-6, 0).

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Updated 2026-04-21

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