Answer:
x = ± sqrt(43)
Step-by-step explanation:
2x^2 - 28 = x^2 + 15
Subtract x^2 from each side
2x^2-x^2 - 28 = x^2-x^2 + 15
x^2 -28 = 15
Add 28 to each side
x^2 - 28 +28= 15+28
x^2 = 43
Take the square root of each side
sqrt(x^2) = ± sqrt(43)
x = ± sqrt(43)
