Solve for x
x=5
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2x+1+2+x+3=21
Combine x and x to get 2x.
2x+3+x+3=21
Add 1 and 2 to get 3.
3x+3+3=21
Combine 2x and x to get 3x.
3x+6=21
Add 3 and 3 to get 6.
3x=21-6
Subtract 6 from both sides.
3x=15
Subtract 6 from 21 to get 15.
x=\frac{15}{3}
Divide both sides by 3.
x=5
Divide 15 by 3 to get 5.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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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
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