Solve for x
x=-15
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21-5x=3\times 2\left(-x+1\right)
Multiply both sides of the equation by 6, the least common multiple of 6,2.
21-5x=6\left(-x+1\right)
Multiply 3 and 2 to get 6.
21-5x=6\left(-x\right)+6
Use the distributive property to multiply 6 by -x+1.
21-5x-6\left(-x\right)=6
Subtract 6\left(-x\right) from both sides.
21-5x-6\left(-1\right)x=6
Multiply -1 and 6 to get -6.
21-5x+6x=6
Multiply -6 and -1 to get 6.
21+x=6
Combine -5x and 6x to get x.
x=6-21
Subtract 21 from both sides.
x=-15
Subtract 21 from 6 to get -15.
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