Solve for x
x=3
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\left(x-2\right)\left(x+7\right)+\left(x+2\right)\times 7=\left(x+2\right)\left(2x+3\right)
Variable x cannot be equal to any of the values -2,2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)\left(x+2\right), the least common multiple of x+2,x-2.
x^{2}+5x-14+\left(x+2\right)\times 7=\left(x+2\right)\left(2x+3\right)
Use the distributive property to multiply x-2 by x+7 and combine like terms.
x^{2}+5x-14+7x+14=\left(x+2\right)\left(2x+3\right)
Use the distributive property to multiply x+2 by 7.
x^{2}+12x-14+14=\left(x+2\right)\left(2x+3\right)
Combine 5x and 7x to get 12x.
x^{2}+12x=\left(x+2\right)\left(2x+3\right)
Add -14 and 14 to get 0.
x^{2}+12x=2x^{2}+7x+6
Use the distributive property to multiply x+2 by 2x+3 and combine like terms.
x^{2}+12x-2x^{2}=7x+6
Subtract 2x^{2} from both sides.
-x^{2}+12x=7x+6
Combine x^{2} and -2x^{2} to get -x^{2}.
-x^{2}+12x-7x=6
Subtract 7x from both sides.
-x^{2}+5x=6
Combine 12x and -7x to get 5x.
-x^{2}+5x-6=0
Subtract 6 from both sides.
x=\frac{-5±\sqrt{5^{2}-4\left(-1\right)\left(-6\right)}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 5 for b, and -6 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-5±\sqrt{25-4\left(-1\right)\left(-6\right)}}{2\left(-1\right)}
Square 5.
x=\frac{-5±\sqrt{25+4\left(-6\right)}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{-5±\sqrt{25-24}}{2\left(-1\right)}
Multiply 4 times -6.
x=\frac{-5±\sqrt{1}}{2\left(-1\right)}
Add 25 to -24.
x=\frac{-5±1}{2\left(-1\right)}
Take the square root of 1.
x=\frac{-5±1}{-2}
Multiply 2 times -1.
x=-\frac{4}{-2}
Now solve the equation x=\frac{-5±1}{-2} when ± is plus. Add -5 to 1.
x=2
Divide -4 by -2.
x=-\frac{6}{-2}
Now solve the equation x=\frac{-5±1}{-2} when ± is minus. Subtract 1 from -5.
x=3
Divide -6 by -2.
x=2 x=3
The equation is now solved.
x=3
Variable x cannot be equal to 2.
\left(x-2\right)\left(x+7\right)+\left(x+2\right)\times 7=\left(x+2\right)\left(2x+3\right)
Variable x cannot be equal to any of the values -2,2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)\left(x+2\right), the least common multiple of x+2,x-2.
x^{2}+5x-14+\left(x+2\right)\times 7=\left(x+2\right)\left(2x+3\right)
Use the distributive property to multiply x-2 by x+7 and combine like terms.
x^{2}+5x-14+7x+14=\left(x+2\right)\left(2x+3\right)
Use the distributive property to multiply x+2 by 7.
x^{2}+12x-14+14=\left(x+2\right)\left(2x+3\right)
Combine 5x and 7x to get 12x.
x^{2}+12x=\left(x+2\right)\left(2x+3\right)
Add -14 and 14 to get 0.
x^{2}+12x=2x^{2}+7x+6
Use the distributive property to multiply x+2 by 2x+3 and combine like terms.
x^{2}+12x-2x^{2}=7x+6
Subtract 2x^{2} from both sides.
-x^{2}+12x=7x+6
Combine x^{2} and -2x^{2} to get -x^{2}.
-x^{2}+12x-7x=6
Subtract 7x from both sides.
-x^{2}+5x=6
Combine 12x and -7x to get 5x.
\frac{-x^{2}+5x}{-1}=\frac{6}{-1}
Divide both sides by -1.
x^{2}+\frac{5}{-1}x=\frac{6}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}-5x=\frac{6}{-1}
Divide 5 by -1.
x^{2}-5x=-6
Divide 6 by -1.
x^{2}-5x+\left(-\frac{5}{2}\right)^{2}=-6+\left(-\frac{5}{2}\right)^{2}
Divide -5, the coefficient of the x term, by 2 to get -\frac{5}{2}. Then add the square of -\frac{5}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-5x+\frac{25}{4}=-6+\frac{25}{4}
Square -\frac{5}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-5x+\frac{25}{4}=\frac{1}{4}
Add -6 to \frac{25}{4}.
\left(x-\frac{5}{2}\right)^{2}=\frac{1}{4}
Factor x^{2}-5x+\frac{25}{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{5}{2}\right)^{2}}=\sqrt{\frac{1}{4}}
Take the square root of both sides of the equation.
x-\frac{5}{2}=\frac{1}{2} x-\frac{5}{2}=-\frac{1}{2}
Simplify.
x=3 x=2
Add \frac{5}{2} to both sides of the equation.
x=3
Variable x cannot be equal to 2.
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