Solve for x
x=18
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7x-21=5\left(x+3\right)
Use the distributive property to multiply 7 by x-3.
7x-21=5x+15
Use the distributive property to multiply 5 by x+3.
7x-21-5x=15
Subtract 5x from both sides.
2x-21=15
Combine 7x and -5x to get 2x.
2x=15+21
Add 21 to both sides.
2x=36
Add 15 and 21 to get 36.
x=\frac{36}{2}
Divide both sides by 2.
x=18
Divide 36 by 2 to get 18.
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