9x^2-81=0

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Solution for 9x^2-81=0 equation:


Simplifying
9x2 + -81 = 0

Reorder the terms:
-81 + 9x2 = 0

Solving
-81 + 9x2 = 0

Solving for variable 'x'.

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

Add '81' to each side of the equation.
-81 + 81 + 9x2 = 0 + 81

Combine like terms: -81 + 81 = 0
0 + 9x2 = 0 + 81
9x2 = 0 + 81

Combine like terms: 0 + 81 = 81
9x2 = 81

Divide each side by '9'.
x2 = 9

Simplifying
x2 = 9

Take the square root of each side:
x = {-3, 3}

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