Solve for x
x=17
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21=x+4
The opposite of -4 is 4.
x+4=21
Swap sides so that all variable terms are on the left hand side.
x=21-4
Subtract 4 from both sides.
x=17
Subtract 4 from 21 to get 17.
Examples
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Matrix
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\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
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Limits
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