Solve for u
u=21
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30=u+9
Multiply both sides of the equation by 3.
u+9=30
Swap sides so that all variable terms are on the left hand side.
u=30-9
Subtract 9 from both sides.
u=21
Subtract 9 from 30 to get 21.
Examples
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Matrix
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Simultaneous equation
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\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
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Limits
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