81x^2+90x+21=0

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Solution for 81x^2+90x+21=0 equation:


Simplifying
81x2 + 90x + 21 = 0

Reorder the terms:
21 + 90x + 81x2 = 0

Solving
21 + 90x + 81x2 = 0

Solving for variable 'x'.

Factor out the Greatest Common Factor (GCF), '3'.
3(7 + 30x + 27x2) = 0

Factor a trinomial.
3((7 + 9x)(1 + 3x)) = 0

Ignore the factor 3.

Subproblem 1

Set the factor '(7 + 9x)' equal to zero and attempt to solve: Simplifying 7 + 9x = 0 Solving 7 + 9x = 0 Move all terms containing x to the left, all other terms to the right. Add '-7' to each side of the equation. 7 + -7 + 9x = 0 + -7 Combine like terms: 7 + -7 = 0 0 + 9x = 0 + -7 9x = 0 + -7 Combine like terms: 0 + -7 = -7 9x = -7 Divide each side by '9'. x = -0.7777777778 Simplifying x = -0.7777777778

Subproblem 2

Set the factor '(1 + 3x)' equal to zero and attempt to solve: Simplifying 1 + 3x = 0 Solving 1 + 3x = 0 Move all terms containing x to the left, all other terms to the right. Add '-1' to each side of the equation. 1 + -1 + 3x = 0 + -1 Combine like terms: 1 + -1 = 0 0 + 3x = 0 + -1 3x = 0 + -1 Combine like terms: 0 + -1 = -1 3x = -1 Divide each side by '3'. x = -0.3333333333 Simplifying x = -0.3333333333

Solution

x = {-0.7777777778, -0.3333333333}

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