Solve for b
b=1
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\frac{-4.2}{-0.84}=b+4
Divide both sides by -0.84.
\frac{-420}{-84}=b+4
Expand \frac{-4.2}{-0.84} by multiplying both numerator and the denominator by 100.
5=b+4
Divide -420 by -84 to get 5.
b+4=5
Swap sides so that all variable terms are on the left hand side.
b=5-4
Subtract 4 from both sides.
b=1
Subtract 4 from 5 to get 1.
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