Solve for x
x = \frac{9}{7} = 1\frac{2}{7} \approx 1.285714286
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-2x-21=-9x-12
Multiply both sides of the equation by 3.
-2x-21+9x=-12
Add 9x to both sides.
7x-21=-12
Combine -2x and 9x to get 7x.
7x=-12+21
Add 21 to both sides.
7x=9
Add -12 and 21 to get 9.
x=\frac{9}{7}
Divide both sides by 7.
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