Solve by completing the square

Solve by completing the square. Leave surds in your answer if needed:

1. x² + 4x - 5 = 0
2. x² - 6x + 7 = 0
3. x² + 2x + 2 = 0
4. 2x² + 8x - 10 = 0
5. x² - 10x + 18 = 0

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