# Solve By Completing the Square

Solve each equation by Completing the Square.

Click “Show Answer” underneath the problem to see the answer. Or click the “Show Answers” button at the bottom of the page to see all the answers at once.

If you need assistance with a particular problem, click the “step-by-step” link for an in depth solution.

## Example:

`Equation: x^2 + x - 3.75 = 0 `
`Answer: x = -2.5, 1.5`

## Quiz:

1. `Equation: x^2 + 5x + 6 = 0 `
`Answer: x = -3, -2`

2. `Equation: x^2 + 2x + 1 = 0 `
`Answer: x = -1`

3. `Equation: x^2 + 3x - 10 = 0 `
`Answer: x = -5, 2`

4. `Equation: m^2 - 4m - 21 = 0 `
`Answer: m = -3, 7`

5. `Equation: 3k^2 + 18k + 15 = 0 `
`Answer: k = -5, -1`

6. `Equation: 2n^2 - 22n + 60 = 0 `
`Answer: n = 5, 6`

7. `Equation: 4y^2 + 8y - 21 = 0 `
`Answer: y = -3.5, 1.5`

8. `Equation: 8y^2 + 10y - 3 = 0 `
`Answer: y = -1.5, 0.25`

9. `Equation: 50k^2 - 20k - 6 = 0 `
`Answer: k = -0.2, 0.6`

10. `Equation: 100x^2 - 100x + 9 = 0 `
`Answer: x = 0.1, 0.9`

11. `Equation: 10t^2 = t + 2 `
`Answer: t = -0.4, 0.5`

12. `Equation: 18m^2 + 6m + 6 = 6m^2 + 30m - 3 `
`Answer: m = 0.5, 1.5`

13. `Equation: p^2 - 0.75p + 0.125 = 0 `
`Answer: p = 0.25, 0.5`

14. `Equation: 2x^2 = x^2 + 1.75 - 3x `
`Answer: x = -3.5, 0.5`

15. `Equation: x^2 = 0.6x - 0.08 `
`Answer: x = 0.2, 0.4`

16. `Equation: 3y^2 - 2.55y - 1.0 = 0.5 `
`Answer: y = -0.4, 1.25`

17. `Equation: j^2 - 3.5j + 1.5 = 0 `
`Answer: j = 0.5, 3`

18. `Equation: c^2 + 3.75c - 1 = 0 `
`Answer: c = -4, 0.25`

19. `Equation: w^2 + 10.1w + 1 = 0 `
`Answer: w = -10, -0.1`

20. `Equation: x^2 -11.5x - 6 = 0 `
`Answer: x = -0.5, 12`

## Related Pages

Completing the Square Lesson

Brush up on your knowledge of the techniques needed to solve problems on this page.

Completing the Square Calculator

Solves equations by completing the square whenever possible.

## Tutoring

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