3x^2-24+21=0

Solution for 3x^2-24+21=0 equation:

Simplifying
3x2 + -24 + 21 = 0

Reorder the terms:
-24 + 21 + 3x2 = 0

Combine like terms: -24 + 21 = -3
-3 + 3x2 = 0

Solving
-3 + 3x2 = 0

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '3' to each side of the equation.
-3 + 3 + 3x2 = 0 + 3

Combine like terms: -3 + 3 = 0
0 + 3x2 = 0 + 3
3x2 = 0 + 3

Combine like terms: 0 + 3 = 3
3x2 = 3

Divide each side by '3'.
x2 = 1

Simplifying
x2 = 1

Take the square root of each side:
x = {-1, 1}