Solve for x
x=-3.2
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-4x-3.8=9
Swap sides so that all variable terms are on the left hand side.
-4x=9+3.8
Add 3.8 to both sides.
-4x=12.8
Add 9 and 3.8 to get 12.8.
x=\frac{12.8}{-4}
Divide both sides by -4.
x=\frac{128}{-40}
Expand \frac{12.8}{-4} by multiplying both numerator and the denominator by 10.
x=-\frac{16}{5}
Reduce the fraction \frac{128}{-40} to lowest terms by extracting and canceling out 8.
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