Answer:
see explanation
Step-by-step explanation:
1
Given
2x² - 16 = 0 ( add 16 to both sides )
2x² = 16 ( divide both sides by 2 )
x² = 8 ( take the square root of both sides )
x = ± = ± 2
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2
Given
- 5x² + 9 = 0 ( subtract 9 from both sides )
- 5x² = - 9 ( divide both sides by - 5 )
x² = ( take the square root of both sides )
x = ± = ±
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3
Given
6x² - 15 = 27 ( add 15 to both sides )
6x² = 42 ( divide both sides by 6 )
x² = 7 ( take the square root of both sides )
x = ±