Solve for x
x=1
x=6
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\left(x-2\right)\times 6+x+2=\left(x-2\right)\left(x+2\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.
6x-12+x+2=\left(x-2\right)\left(x+2\right)
Use the distributive property to multiply x-2 by 6.
7x-12+2=\left(x-2\right)\left(x+2\right)
Combine 6x and x to get 7x.
7x-10=\left(x-2\right)\left(x+2\right)
Add -12 and 2 to get -10.
7x-10=x^{2}-4
Consider \left(x-2\right)\left(x+2\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 2.
7x-10-x^{2}=-4
Subtract x^{2} from both sides.
7x-10-x^{2}+4=0
Add 4 to both sides.
7x-6-x^{2}=0
Add -10 and 4 to get -6.
-x^{2}+7x-6=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
x=\frac{-7±\sqrt{7^{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, 7 for b, and -6 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-7±\sqrt{49-4\left(-1\right)\left(-6\right)}}{2\left(-1\right)}
Square 7.
x=\frac{-7±\sqrt{49+4\left(-6\right)}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{-7±\sqrt{49-24}}{2\left(-1\right)}
Multiply 4 times -6.
x=\frac{-7±\sqrt{25}}{2\left(-1\right)}
Add 49 to -24.
x=\frac{-7±5}{2\left(-1\right)}
Take the square root of 25.
x=\frac{-7±5}{-2}
Multiply 2 times -1.
x=-\frac{2}{-2}
Now solve the equation x=\frac{-7±5}{-2} when ± is plus. Add -7 to 5.
x=1
Divide -2 by -2.
x=-\frac{12}{-2}
Now solve the equation x=\frac{-7±5}{-2} when ± is minus. Subtract 5 from -7.
x=6
Divide -12 by -2.
x=1 x=6
The equation is now solved.
\left(x-2\right)\times 6+x+2=\left(x-2\right)\left(x+2\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.
6x-12+x+2=\left(x-2\right)\left(x+2\right)
Use the distributive property to multiply x-2 by 6.
7x-12+2=\left(x-2\right)\left(x+2\right)
Combine 6x and x to get 7x.
7x-10=\left(x-2\right)\left(x+2\right)
Add -12 and 2 to get -10.
7x-10=x^{2}-4
Consider \left(x-2\right)\left(x+2\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 2.
7x-10-x^{2}=-4
Subtract x^{2} from both sides.
7x-x^{2}=-4+10
Add 10 to both sides.
7x-x^{2}=6
Add -4 and 10 to get 6.
-x^{2}+7x=6
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
\frac{-x^{2}+7x}{-1}=\frac{6}{-1}
Divide both sides by -1.
x^{2}+\frac{7}{-1}x=\frac{6}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}-7x=\frac{6}{-1}
Divide 7 by -1.
x^{2}-7x=-6
Divide 6 by -1.
x^{2}-7x+\left(-\frac{7}{2}\right)^{2}=-6+\left(-\frac{7}{2}\right)^{2}
Divide -7, the coefficient of the x term, by 2 to get -\frac{7}{2}. Then add the square of -\frac{7}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-7x+\frac{49}{4}=-6+\frac{49}{4}
Square -\frac{7}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-7x+\frac{49}{4}=\frac{25}{4}
Add -6 to \frac{49}{4}.
\left(x-\frac{7}{2}\right)^{2}=\frac{25}{4}
Factor x^{2}-7x+\frac{49}{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{7}{2}\right)^{2}}=\sqrt{\frac{25}{4}}
Take the square root of both sides of the equation.
x-\frac{7}{2}=\frac{5}{2} x-\frac{7}{2}=-\frac{5}{2}
Simplify.
x=6 x=1
Add \frac{7}{2} to both sides of the equation.
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Matrix
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Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
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Integration
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Limits
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