Answers: x = 8 and x = -8
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Work Shown:
x^2 + 15 = 79
x^2 = 79-15
x^2 = 64
x = sqrt(64) or x = -sqrt(64)
x = 8 or x = -8
As the steps above show, we first subtract 15 from both sides. Then we apply the square root to get the two results. Don't forget about the plus minus.