Math Practice Online > free > lessons > Florida > 9th grade > Quadratic X-Intercepts

These sample problems below for Quadratic X-Intercepts were generated by the MathScore.com engine.

## Sample Problems For Quadratic X-Intercepts

### Complexity=1

Find the x-intercepts of each function. Separate multiple answers by commas. Example: x=-3/2,2
If there is no x-intercept, write "none".
 1.   f(x) = x 2 + 16x + 64 x-intercepts: 2.   f(x) = x 2 + 2x + 11 x-intercepts:

### Complexity=1

Find the x-intercepts of each function. Separate multiple answers by commas. Example: x=-3/2,2
If there is no x-intercept, write "none".
1f(x) = x 2 + 16x + 64
x-intercepts:
Solution
To find the x-intercepts, set the trinomial equal to 0.
x 2 + 16x + 64 = 0
Factor the trinomial.
( x + 8) 2 = 0
Solve for x.
x + 8 = 0

Therefore, the x-intercept is -8

Alternate Solution
You can also use the quadratic formula to find the x-intercepts.

2f(x) = x 2 + 2x + 11
x-intercepts:
Solution
To find the x-intercepts, set the trinomial equal to 0.
x 2 + 2x + 11 = 0
Use the quadratic formula to find the x-intercepts.
Based on ax2 + bx + c, we have:
a = 1, b = 2, c = 11