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Simplifying
4x2 + 1 + -81 = 0
Reorder the terms:
1 + -81 + 4x2 = 0
Combine like terms: 1 + -81 = -80
-80 + 4x2 = 0
Solving
-80 + 4x2 = 0
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '80' to each side of the equation.
-80 + 80 + 4x2 = 0 + 80
Combine like terms: -80 + 80 = 0
0 + 4x2 = 0 + 80
4x2 = 0 + 80
Combine like terms: 0 + 80 = 80
4x2 = 80
Divide each side by '4'.
x2 = 20
Simplifying
x2 = 20
Take the square root of each side:
x = {-4.472135955, 4.472135955}
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