Solve for x
x=-1
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2x\left(x+3\right)\times 2-\left(x^{2}-9\right)=2x\left(x-3\right)+x^{2}-9
Variable x cannot be equal to any of the values -3,0,3 since division by zero is not defined. Multiply both sides of the equation by 2x\left(x-3\right)\left(x+3\right), the least common multiple of x-3,2x,x+3.
\left(2x^{2}+6x\right)\times 2-\left(x^{2}-9\right)=2x\left(x-3\right)+x^{2}-9
Use the distributive property to multiply 2x by x+3.
4x^{2}+12x-\left(x^{2}-9\right)=2x\left(x-3\right)+x^{2}-9
Use the distributive property to multiply 2x^{2}+6x by 2.
4x^{2}+12x-x^{2}+9=2x\left(x-3\right)+x^{2}-9
To find the opposite of x^{2}-9, find the opposite of each term.
3x^{2}+12x+9=2x\left(x-3\right)+x^{2}-9
Combine 4x^{2} and -x^{2} to get 3x^{2}.
3x^{2}+12x+9=2x^{2}-6x+x^{2}-9
Use the distributive property to multiply 2x by x-3.
3x^{2}+12x+9=3x^{2}-6x-9
Combine 2x^{2} and x^{2} to get 3x^{2}.
3x^{2}+12x+9-3x^{2}=-6x-9
Subtract 3x^{2} from both sides.
12x+9=-6x-9
Combine 3x^{2} and -3x^{2} to get 0.
12x+9+6x=-9
Add 6x to both sides.
18x+9=-9
Combine 12x and 6x to get 18x.
18x=-9-9
Subtract 9 from both sides.
18x=-18
Subtract 9 from -9 to get -18.
x=\frac{-18}{18}
Divide both sides by 18.
x=-1
Divide -18 by 18 to get -1.
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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
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Limits
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