Answers

2016-06-15T22:31:08+08:00
3 (x² + 7)
equate the equation to 0 &
distribute 3 to x² and 7
3 (x² + 7) = 0
3x² + 21 = 0
3x² = -21
3x²/3 = -21/3
x² = -7
√x = √-7
x = i√7

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