Solve for x
x=5
x=9
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\left(4x-12\right)\left(x-1\right)-\left(2x+6\right)\left(x-4\right)=\left(x-3\right)\left(x+3\right)
Variable x cannot be equal to any of the values -3,3 since division by zero is not defined. Multiply both sides of the equation by 4\left(x-3\right)\left(x+3\right), the least common multiple of x+3,2\left(x-3\right),4.
4x^{2}-16x+12-\left(2x+6\right)\left(x-4\right)=\left(x-3\right)\left(x+3\right)
Use the distributive property to multiply 4x-12 by x-1 and combine like terms.
4x^{2}-16x+12-\left(2x^{2}-2x-24\right)=\left(x-3\right)\left(x+3\right)
Use the distributive property to multiply 2x+6 by x-4 and combine like terms.
4x^{2}-16x+12-2x^{2}+2x+24=\left(x-3\right)\left(x+3\right)
To find the opposite of 2x^{2}-2x-24, find the opposite of each term.
2x^{2}-16x+12+2x+24=\left(x-3\right)\left(x+3\right)
Combine 4x^{2} and -2x^{2} to get 2x^{2}.
2x^{2}-14x+12+24=\left(x-3\right)\left(x+3\right)
Combine -16x and 2x to get -14x.
2x^{2}-14x+36=\left(x-3\right)\left(x+3\right)
Add 12 and 24 to get 36.
2x^{2}-14x+36=x^{2}-9
Consider \left(x-3\right)\left(x+3\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 3.
2x^{2}-14x+36-x^{2}=-9
Subtract x^{2} from both sides.
x^{2}-14x+36=-9
Combine 2x^{2} and -x^{2} to get x^{2}.
x^{2}-14x+36+9=0
Add 9 to both sides.
x^{2}-14x+45=0
Add 36 and 9 to get 45.
x=\frac{-\left(-14\right)±\sqrt{\left(-14\right)^{2}-4\times 45}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -14 for b, and 45 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-14\right)±\sqrt{196-4\times 45}}{2}
Square -14.
x=\frac{-\left(-14\right)±\sqrt{196-180}}{2}
Multiply -4 times 45.
x=\frac{-\left(-14\right)±\sqrt{16}}{2}
Add 196 to -180.
x=\frac{-\left(-14\right)±4}{2}
Take the square root of 16.
x=\frac{14±4}{2}
The opposite of -14 is 14.
x=\frac{18}{2}
Now solve the equation x=\frac{14±4}{2} when ± is plus. Add 14 to 4.
x=9
Divide 18 by 2.
x=\frac{10}{2}
Now solve the equation x=\frac{14±4}{2} when ± is minus. Subtract 4 from 14.
x=5
Divide 10 by 2.
x=9 x=5
The equation is now solved.
\left(4x-12\right)\left(x-1\right)-\left(2x+6\right)\left(x-4\right)=\left(x-3\right)\left(x+3\right)
Variable x cannot be equal to any of the values -3,3 since division by zero is not defined. Multiply both sides of the equation by 4\left(x-3\right)\left(x+3\right), the least common multiple of x+3,2\left(x-3\right),4.
4x^{2}-16x+12-\left(2x+6\right)\left(x-4\right)=\left(x-3\right)\left(x+3\right)
Use the distributive property to multiply 4x-12 by x-1 and combine like terms.
4x^{2}-16x+12-\left(2x^{2}-2x-24\right)=\left(x-3\right)\left(x+3\right)
Use the distributive property to multiply 2x+6 by x-4 and combine like terms.
4x^{2}-16x+12-2x^{2}+2x+24=\left(x-3\right)\left(x+3\right)
To find the opposite of 2x^{2}-2x-24, find the opposite of each term.
2x^{2}-16x+12+2x+24=\left(x-3\right)\left(x+3\right)
Combine 4x^{2} and -2x^{2} to get 2x^{2}.
2x^{2}-14x+12+24=\left(x-3\right)\left(x+3\right)
Combine -16x and 2x to get -14x.
2x^{2}-14x+36=\left(x-3\right)\left(x+3\right)
Add 12 and 24 to get 36.
2x^{2}-14x+36=x^{2}-9
Consider \left(x-3\right)\left(x+3\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 3.
2x^{2}-14x+36-x^{2}=-9
Subtract x^{2} from both sides.
x^{2}-14x+36=-9
Combine 2x^{2} and -x^{2} to get x^{2}.
x^{2}-14x=-9-36
Subtract 36 from both sides.
x^{2}-14x=-45
Subtract 36 from -9 to get -45.
x^{2}-14x+\left(-7\right)^{2}=-45+\left(-7\right)^{2}
Divide -14, the coefficient of the x term, by 2 to get -7. Then add the square of -7 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-14x+49=-45+49
Square -7.
x^{2}-14x+49=4
Add -45 to 49.
\left(x-7\right)^{2}=4
Factor x^{2}-14x+49. 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-7\right)^{2}}=\sqrt{4}
Take the square root of both sides of the equation.
x-7=2 x-7=-2
Simplify.
x=9 x=5
Add 7 to both sides of the equation.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}