Solve for a
a=2
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-2a-\left(-1\right)=3a-9
To find the opposite of 2a-1, find the opposite of each term.
-2a+1=3a-9
The opposite of -1 is 1.
-2a+1-3a=-9
Subtract 3a from both sides.
-5a+1=-9
Combine -2a and -3a to get -5a.
-5a=-9-1
Subtract 1 from both sides.
-5a=-10
Subtract 1 from -9 to get -10.
a=\frac{-10}{-5}
Divide both sides by -5.
a=2
Divide -10 by -5 to get 2.
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