Solve for x
x=28
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4\times 2x-7x=28
Multiply both sides of the equation by 28, the least common multiple of 7,4.
8x-7x=28
Multiply 4 and 2 to get 8.
x=28
Combine 8x and -7x to get x.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
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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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