Answer:
x = ±3
Explanation:
Put both equations equal to each other.
2x + 1 = x^2 - 8
Cancel 2x on both sides.
1 = x^2 - 8
Add 8 to both sides.
1 + 8 = x^2
Simplify 1 + 8 to 9.
9 = x^2
Take the square root of both sides.
±√9 = x
±3=x
Simplify.
x = ±3