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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:

Answers

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".
#ProblemCorrect AnswerYour Answer
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.

#ProblemCorrect AnswerYour Answer
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

Plugging into the quadratic formula results in these two answers:

Simplifying...

Since the square root is not a real number, there are no real number solutions.
Therefore, there are no x-intercepts.

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