# Quadratic Formula Examples

### Example 1

Use the quadratic formula to find the roots of *y* = 2*x*^{2} + 4*x* + 1
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How about we check if you know your abc's? *a *= 2* * b = 4
*c* = 1
if (answer = correct) print("Good job!") else { print("Practice some more and you'll surely get the hang of it.") } Next, we plug our numbers into the quadratic formula. Then, simplify. | |

### Example 2

Use the quadratic formula to find the roots of
*
y* = *x*^{2} – 16
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This is a quadratic function, so we can still use the quadratic formula. *a* = 1
*b* = 0
*c* = -16
We just have *b* = 0. Everything works out the same otherwise. And done. | |

### Example 3

Use the quadratic formula to find the roots of
*
y* = *x*^{2} + 4*x* + 4
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*a* = 1
*b* = 4
*c* = 4
Third verse, same as the first. There is only one real root for this equation. | |

### Example 4

Use the quadratic formula to find the roots of . | |

*b* = 3
*c* = 6
In this case we have two complex roots. | |

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