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Solve for x (complex solution)
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\left(x+5\right)\left(x+3\right)=2x\left(x+7\right)-2
Subtract 2 from 7 to get 5.
x^{2}+8x+15=2x\left(x+7\right)-2
Use the distributive property to multiply x+5 by x+3 and combine like terms.
x^{2}+8x+15=2x^{2}+14x-2
Use the distributive property to multiply 2x by x+7.
x^{2}+8x+15-2x^{2}=14x-2
Subtract 2x^{2} from both sides.
-x^{2}+8x+15=14x-2
Combine x^{2} and -2x^{2} to get -x^{2}.
-x^{2}+8x+15-14x=-2
Subtract 14x from both sides.
-x^{2}-6x+15=-2
Combine 8x and -14x to get -6x.
-x^{2}-6x+15+2=0
Add 2 to both sides.
-x^{2}-6x+17=0
Add 15 and 2 to get 17.
x=\frac{-\left(-6\right)±\sqrt{\left(-6\right)^{2}-4\left(-1\right)\times 17}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, -6 for b, and 17 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-6\right)±\sqrt{36-4\left(-1\right)\times 17}}{2\left(-1\right)}
Square -6.
x=\frac{-\left(-6\right)±\sqrt{36+4\times 17}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{-\left(-6\right)±\sqrt{36+68}}{2\left(-1\right)}
Multiply 4 times 17.
x=\frac{-\left(-6\right)±\sqrt{104}}{2\left(-1\right)}
Add 36 to 68.
x=\frac{-\left(-6\right)±2\sqrt{26}}{2\left(-1\right)}
Take the square root of 104.
x=\frac{6±2\sqrt{26}}{2\left(-1\right)}
The opposite of -6 is 6.
x=\frac{6±2\sqrt{26}}{-2}
Multiply 2 times -1.
x=\frac{2\sqrt{26}+6}{-2}
Now solve the equation x=\frac{6±2\sqrt{26}}{-2} when ± is plus. Add 6 to 2\sqrt{26}.
x=-\left(\sqrt{26}+3\right)
Divide 6+2\sqrt{26} by -2.
x=\frac{6-2\sqrt{26}}{-2}
Now solve the equation x=\frac{6±2\sqrt{26}}{-2} when ± is minus. Subtract 2\sqrt{26} from 6.
x=\sqrt{26}-3
Divide 6-2\sqrt{26} by -2.
x=-\left(\sqrt{26}+3\right) x=\sqrt{26}-3
The equation is now solved.
\left(x+5\right)\left(x+3\right)=2x\left(x+7\right)-2
Subtract 2 from 7 to get 5.
x^{2}+8x+15=2x\left(x+7\right)-2
Use the distributive property to multiply x+5 by x+3 and combine like terms.
x^{2}+8x+15=2x^{2}+14x-2
Use the distributive property to multiply 2x by x+7.
x^{2}+8x+15-2x^{2}=14x-2
Subtract 2x^{2} from both sides.
-x^{2}+8x+15=14x-2
Combine x^{2} and -2x^{2} to get -x^{2}.
-x^{2}+8x+15-14x=-2
Subtract 14x from both sides.
-x^{2}-6x+15=-2
Combine 8x and -14x to get -6x.
-x^{2}-6x=-2-15
Subtract 15 from both sides.
-x^{2}-6x=-17
Subtract 15 from -2 to get -17.
\frac{-x^{2}-6x}{-1}=-\frac{17}{-1}
Divide both sides by -1.
x^{2}+\left(-\frac{6}{-1}\right)x=-\frac{17}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}+6x=-\frac{17}{-1}
Divide -6 by -1.
x^{2}+6x=17
Divide -17 by -1.
x^{2}+6x+3^{2}=17+3^{2}
Divide 6, the coefficient of the x term, by 2 to get 3. Then add the square of 3 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+6x+9=17+9
Square 3.
x^{2}+6x+9=26
Add 17 to 9.
\left(x+3\right)^{2}=26
Factor x^{2}+6x+9. 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+3\right)^{2}}=\sqrt{26}
Take the square root of both sides of the equation.
x+3=\sqrt{26} x+3=-\sqrt{26}
Simplify.
x=\sqrt{26}-3 x=-\sqrt{26}-3
Subtract 3 from both sides of the equation.
\left(x+5\right)\left(x+3\right)=2x\left(x+7\right)-2
Subtract 2 from 7 to get 5.
x^{2}+8x+15=2x\left(x+7\right)-2
Use the distributive property to multiply x+5 by x+3 and combine like terms.
x^{2}+8x+15=2x^{2}+14x-2
Use the distributive property to multiply 2x by x+7.
x^{2}+8x+15-2x^{2}=14x-2
Subtract 2x^{2} from both sides.
-x^{2}+8x+15=14x-2
Combine x^{2} and -2x^{2} to get -x^{2}.
-x^{2}+8x+15-14x=-2
Subtract 14x from both sides.
-x^{2}-6x+15=-2
Combine 8x and -14x to get -6x.
-x^{2}-6x+15+2=0
Add 2 to both sides.
-x^{2}-6x+17=0
Add 15 and 2 to get 17.
x=\frac{-\left(-6\right)±\sqrt{\left(-6\right)^{2}-4\left(-1\right)\times 17}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, -6 for b, and 17 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-6\right)±\sqrt{36-4\left(-1\right)\times 17}}{2\left(-1\right)}
Square -6.
x=\frac{-\left(-6\right)±\sqrt{36+4\times 17}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{-\left(-6\right)±\sqrt{36+68}}{2\left(-1\right)}
Multiply 4 times 17.
x=\frac{-\left(-6\right)±\sqrt{104}}{2\left(-1\right)}
Add 36 to 68.
x=\frac{-\left(-6\right)±2\sqrt{26}}{2\left(-1\right)}
Take the square root of 104.
x=\frac{6±2\sqrt{26}}{2\left(-1\right)}
The opposite of -6 is 6.
x=\frac{6±2\sqrt{26}}{-2}
Multiply 2 times -1.
x=\frac{2\sqrt{26}+6}{-2}
Now solve the equation x=\frac{6±2\sqrt{26}}{-2} when ± is plus. Add 6 to 2\sqrt{26}.
x=-\left(\sqrt{26}+3\right)
Divide 6+2\sqrt{26} by -2.
x=\frac{6-2\sqrt{26}}{-2}
Now solve the equation x=\frac{6±2\sqrt{26}}{-2} when ± is minus. Subtract 2\sqrt{26} from 6.
x=\sqrt{26}-3
Divide 6-2\sqrt{26} by -2.
x=-\left(\sqrt{26}+3\right) x=\sqrt{26}-3
The equation is now solved.
\left(x+5\right)\left(x+3\right)=2x\left(x+7\right)-2
Subtract 2 from 7 to get 5.
x^{2}+8x+15=2x\left(x+7\right)-2
Use the distributive property to multiply x+5 by x+3 and combine like terms.
x^{2}+8x+15=2x^{2}+14x-2
Use the distributive property to multiply 2x by x+7.
x^{2}+8x+15-2x^{2}=14x-2
Subtract 2x^{2} from both sides.
-x^{2}+8x+15=14x-2
Combine x^{2} and -2x^{2} to get -x^{2}.
-x^{2}+8x+15-14x=-2
Subtract 14x from both sides.
-x^{2}-6x+15=-2
Combine 8x and -14x to get -6x.
-x^{2}-6x=-2-15
Subtract 15 from both sides.
-x^{2}-6x=-17
Subtract 15 from -2 to get -17.
\frac{-x^{2}-6x}{-1}=-\frac{17}{-1}
Divide both sides by -1.
x^{2}+\left(-\frac{6}{-1}\right)x=-\frac{17}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}+6x=-\frac{17}{-1}
Divide -6 by -1.
x^{2}+6x=17
Divide -17 by -1.
x^{2}+6x+3^{2}=17+3^{2}
Divide 6, the coefficient of the x term, by 2 to get 3. Then add the square of 3 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+6x+9=17+9
Square 3.
x^{2}+6x+9=26
Add 17 to 9.
\left(x+3\right)^{2}=26
Factor x^{2}+6x+9. 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+3\right)^{2}}=\sqrt{26}
Take the square root of both sides of the equation.
x+3=\sqrt{26} x+3=-\sqrt{26}
Simplify.
x=\sqrt{26}-3 x=-\sqrt{26}-3
Subtract 3 from both sides of the equation.