Solve for x
x=7
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5x-\left(x^{2}-4x+4\right)-3\left(2x+5\right)=4\left(-1\right)-\left(x-1\right)\left(x+1\right)+5
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
5x-x^{2}+4x-4-3\left(2x+5\right)=4\left(-1\right)-\left(x-1\right)\left(x+1\right)+5
To find the opposite of x^{2}-4x+4, find the opposite of each term.
9x-x^{2}-4-3\left(2x+5\right)=4\left(-1\right)-\left(x-1\right)\left(x+1\right)+5
Combine 5x and 4x to get 9x.
9x-x^{2}-4-6x-15=4\left(-1\right)-\left(x-1\right)\left(x+1\right)+5
Use the distributive property to multiply -3 by 2x+5.
3x-x^{2}-4-15=4\left(-1\right)-\left(x-1\right)\left(x+1\right)+5
Combine 9x and -6x to get 3x.
3x-x^{2}-19=4\left(-1\right)-\left(x-1\right)\left(x+1\right)+5
Subtract 15 from -4 to get -19.
3x-x^{2}-19=-4-\left(x-1\right)\left(x+1\right)+5
Multiply 4 and -1 to get -4.
3x-x^{2}-19=-4-\left(x^{2}-1\right)+5
Consider \left(x-1\right)\left(x+1\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 1.
3x-x^{2}-19=-4-x^{2}+1+5
To find the opposite of x^{2}-1, find the opposite of each term.
3x-x^{2}-19=-3-x^{2}+5
Add -4 and 1 to get -3.
3x-x^{2}-19=2-x^{2}
Add -3 and 5 to get 2.
3x-x^{2}-19+x^{2}=2
Add x^{2} to both sides.
3x-19=2
Combine -x^{2} and x^{2} to get 0.
3x=2+19
Add 19 to both sides.
3x=21
Add 2 and 19 to get 21.
x=\frac{21}{3}
Divide both sides by 3.
x=7
Divide 21 by 3 to get 7.
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}