3x^2+18=21

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Solution for 3x^2+18=21 equation: 


Simplifying
3x2 + 18 = 21

Reorder the terms:
18 + 3x2 = 21

Solving
18 + 3x2 = 21

Solving for variable 'x'.

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

Add '-18' to each side of the equation.
18 + -18 + 3x2 = 21 + -18

Combine like terms: 18 + -18 = 0
0 + 3x2 = 21 + -18
3x2 = 21 + -18

Combine like terms: 21 + -18 = 3
3x2 = 3

Divide each side by '3'.
x2 = 1

Simplifying
x2 = 1

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

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