Solve for a
a = \frac{7}{2} = 3\frac{1}{2} = 3.5
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-4-\left(-2a\right)=3
Multiply 2 and -2 to get -4.
-4+2a=3
The opposite of -2a is 2a.
2a=3+4
Add 4 to both sides.
2a=7
Add 3 and 4 to get 7.
a=\frac{7}{2}
Divide both sides by 2.
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