Example

Finding the Intercepts of y=−x2−12x−36y = -x^2 - 12x - 36

To find the intercepts of the parabola y=−x2−12x−36y = -x^2 - 12x - 36:

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

y=−(0)2−12(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=−x2−12x−360 = -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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