Solve for x
x = -\frac{8}{3} = -2\frac{2}{3} \approx -2.666666667
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\left(2x\right)^{2}-9=\left(4x-1\right)\left(x+1\right)
Consider \left(2x+3\right)\left(2x-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.
2^{2}x^{2}-9=\left(4x-1\right)\left(x+1\right)
Expand \left(2x\right)^{2}.
4x^{2}-9=\left(4x-1\right)\left(x+1\right)
Calculate 2 to the power of 2 and get 4.
4x^{2}-9=4x^{2}+3x-1
Use the distributive property to multiply 4x-1 by x+1 and combine like terms.
4x^{2}-9-4x^{2}=3x-1
Subtract 4x^{2} from both sides.
-9=3x-1
Combine 4x^{2} and -4x^{2} to get 0.
3x-1=-9
Swap sides so that all variable terms are on the left hand side.
3x=-9+1
Add 1 to both sides.
3x=-8
Add -9 and 1 to get -8.
x=\frac{-8}{3}
Divide both sides by 3.
x=-\frac{8}{3}
Fraction \frac{-8}{3} can be rewritten as -\frac{8}{3} by extracting the negative sign.
Examples
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y = 3x + 4
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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
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