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\left(x+3\right)\left(x-1\right)=3\left(x+1\right)
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.
x^{2}+2x-3=3\left(x+1\right)
Use the distributive property to multiply x+3 by x-1 and combine like terms.
x^{2}+2x-3=3x+3
Use the distributive property to multiply 3 by x+1.
x^{2}+2x-3-3x=3
Subtract 3x from both sides.
x^{2}-x-3=3
Combine 2x and -3x to get -x.
x^{2}-x-3-3=0
Subtract 3 from both sides.
x^{2}-x-6=0
Subtract 3 from -3 to get -6.
x=\frac{-\left(-1\right)±\sqrt{1-4\left(-6\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -1 for b, and -6 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-1\right)±\sqrt{1+24}}{2}
Multiply -4 times -6.
x=\frac{-\left(-1\right)±\sqrt{25}}{2}
Add 1 to 24.
x=\frac{-\left(-1\right)±5}{2}
Take the square root of 25.
x=\frac{1±5}{2}
The opposite of -1 is 1.
x=\frac{6}{2}
Now solve the equation x=\frac{1±5}{2} when ± is plus. Add 1 to 5.
x=3
Divide 6 by 2.
x=-\frac{4}{2}
Now solve the equation x=\frac{1±5}{2} when ± is minus. Subtract 5 from 1.
x=-2
Divide -4 by 2.
x=3 x=-2
The equation is now solved.
\left(x+3\right)\left(x-1\right)=3\left(x+1\right)
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.
x^{2}+2x-3=3\left(x+1\right)
Use the distributive property to multiply x+3 by x-1 and combine like terms.
x^{2}+2x-3=3x+3
Use the distributive property to multiply 3 by x+1.
x^{2}+2x-3-3x=3
Subtract 3x from both sides.
x^{2}-x-3=3
Combine 2x and -3x to get -x.
x^{2}-x=3+3
Add 3 to both sides.
x^{2}-x=6
Add 3 and 3 to get 6.
x^{2}-x+\left(-\frac{1}{2}\right)^{2}=6+\left(-\frac{1}{2}\right)^{2}
Divide -1, the coefficient of the x term, by 2 to get -\frac{1}{2}. Then add the square of -\frac{1}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-x+\frac{1}{4}=6+\frac{1}{4}
Square -\frac{1}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-x+\frac{1}{4}=\frac{25}{4}
Add 6 to \frac{1}{4}.
\left(x-\frac{1}{2}\right)^{2}=\frac{25}{4}
Factor x^{2}-x+\frac{1}{4}. 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{1}{2}\right)^{2}}=\sqrt{\frac{25}{4}}
Take the square root of both sides of the equation.
x-\frac{1}{2}=\frac{5}{2} x-\frac{1}{2}=-\frac{5}{2}
Simplify.
x=3 x=-2
Add \frac{1}{2} to both sides of the equation.