Solve for x
x=18
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7x-21=105
Swap sides so that all variable terms are on the left hand side.
7x=105+21
Add 21 to both sides.
7x=126
Add 105 and 21 to get 126.
x=\frac{126}{7}
Divide both sides by 7.
x=18
Divide 126 by 7 to get 18.
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