Solve for x
x = \frac{\sqrt{229} - 7}{6} \approx 1.355457658
x=\frac{-\sqrt{229}-7}{6}\approx -3.688790992
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\left(x+3\right)\left(3x-2\right)=3\times 3
Variable x cannot be equal to -3 since division by zero is not defined. Multiply both sides of the equation by 3\left(x+3\right), the least common multiple of 3,x+3.
3x^{2}+7x-6=3\times 3
Use the distributive property to multiply x+3 by 3x-2 and combine like terms.
3x^{2}+7x-6=9
Multiply 3 and 3 to get 9.
3x^{2}+7x-6-9=0
Subtract 9 from both sides.
3x^{2}+7x-15=0
Subtract 9 from -6 to get -15.
x=\frac{-7±\sqrt{7^{2}-4\times 3\left(-15\right)}}{2\times 3}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 3 for a, 7 for b, and -15 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-7±\sqrt{49-4\times 3\left(-15\right)}}{2\times 3}
Square 7.
x=\frac{-7±\sqrt{49-12\left(-15\right)}}{2\times 3}
Multiply -4 times 3.
x=\frac{-7±\sqrt{49+180}}{2\times 3}
Multiply -12 times -15.
x=\frac{-7±\sqrt{229}}{2\times 3}
Add 49 to 180.
x=\frac{-7±\sqrt{229}}{6}
Multiply 2 times 3.
x=\frac{\sqrt{229}-7}{6}
Now solve the equation x=\frac{-7±\sqrt{229}}{6} when ± is plus. Add -7 to \sqrt{229}.
x=\frac{-\sqrt{229}-7}{6}
Now solve the equation x=\frac{-7±\sqrt{229}}{6} when ± is minus. Subtract \sqrt{229} from -7.
x=\frac{\sqrt{229}-7}{6} x=\frac{-\sqrt{229}-7}{6}
The equation is now solved.
\left(x+3\right)\left(3x-2\right)=3\times 3
Variable x cannot be equal to -3 since division by zero is not defined. Multiply both sides of the equation by 3\left(x+3\right), the least common multiple of 3,x+3.
3x^{2}+7x-6=3\times 3
Use the distributive property to multiply x+3 by 3x-2 and combine like terms.
3x^{2}+7x-6=9
Multiply 3 and 3 to get 9.
3x^{2}+7x=9+6
Add 6 to both sides.
3x^{2}+7x=15
Add 9 and 6 to get 15.
\frac{3x^{2}+7x}{3}=\frac{15}{3}
Divide both sides by 3.
x^{2}+\frac{7}{3}x=\frac{15}{3}
Dividing by 3 undoes the multiplication by 3.
x^{2}+\frac{7}{3}x=5
Divide 15 by 3.
x^{2}+\frac{7}{3}x+\left(\frac{7}{6}\right)^{2}=5+\left(\frac{7}{6}\right)^{2}
Divide \frac{7}{3}, the coefficient of the x term, by 2 to get \frac{7}{6}. Then add the square of \frac{7}{6} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{7}{3}x+\frac{49}{36}=5+\frac{49}{36}
Square \frac{7}{6} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{7}{3}x+\frac{49}{36}=\frac{229}{36}
Add 5 to \frac{49}{36}.
\left(x+\frac{7}{6}\right)^{2}=\frac{229}{36}
Factor x^{2}+\frac{7}{3}x+\frac{49}{36}. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(x+\frac{7}{6}\right)^{2}}=\sqrt{\frac{229}{36}}
Take the square root of both sides of the equation.
x+\frac{7}{6}=\frac{\sqrt{229}}{6} x+\frac{7}{6}=-\frac{\sqrt{229}}{6}
Simplify.
x=\frac{\sqrt{229}-7}{6} x=\frac{-\sqrt{229}-7}{6}
Subtract \frac{7}{6} from both sides of the equation.
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