Solve for x
x=15
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2x-9=3\times 7
Divide 18 by 2 to get 9.
2x-9=21
Multiply 3 and 7 to get 21.
2x=21+9
Add 9 to both sides.
2x=30
Add 21 and 9 to get 30.
x=\frac{30}{2}
Divide both sides by 2.
x=15
Divide 30 by 2 to get 15.
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