Solve for x
x=3
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2x+1=\frac{21}{3}
Divide both sides by 3.
2x+1=7
Divide 21 by 3 to get 7.
2x=7-1
Subtract 1 from both sides.
2x=6
Subtract 1 from 7 to get 6.
x=\frac{6}{2}
Divide both sides by 2.
x=3
Divide 6 by 2 to get 3.
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