Solve for x
x=18
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5x=90
Combine 4x and x to get 5x.
x=\frac{90}{5}
Divide both sides by 5.
x=18
Divide 90 by 5 to get 18.
Examples
Quadratic equation
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4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
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Matrix
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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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