Solve for x
x=4
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4-x^{2}+\left(2x-5\right)^{2}=3\left(1-x\right)\left(5-x\right)+6
Consider \left(2-x\right)\left(2+x\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.
4-x^{2}+4x^{2}-20x+25=3\left(1-x\right)\left(5-x\right)+6
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(2x-5\right)^{2}.
4+3x^{2}-20x+25=3\left(1-x\right)\left(5-x\right)+6
Combine -x^{2} and 4x^{2} to get 3x^{2}.
29+3x^{2}-20x=3\left(1-x\right)\left(5-x\right)+6
Add 4 and 25 to get 29.
29+3x^{2}-20x=\left(3-3x\right)\left(5-x\right)+6
Use the distributive property to multiply 3 by 1-x.
29+3x^{2}-20x=15-18x+3x^{2}+6
Use the distributive property to multiply 3-3x by 5-x and combine like terms.
29+3x^{2}-20x=21-18x+3x^{2}
Add 15 and 6 to get 21.
29+3x^{2}-20x+18x=21+3x^{2}
Add 18x to both sides.
29+3x^{2}-2x=21+3x^{2}
Combine -20x and 18x to get -2x.
29+3x^{2}-2x-3x^{2}=21
Subtract 3x^{2} from both sides.
29-2x=21
Combine 3x^{2} and -3x^{2} to get 0.
-2x=21-29
Subtract 29 from both sides.
-2x=-8
Subtract 29 from 21 to get -8.
x=\frac{-8}{-2}
Divide both sides by -2.
x=4
Divide -8 by -2 to get 4.
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}