Solve for b
b=2
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5=\frac{-3\left(-7\right)}{7}+b
Express -\frac{3}{7}\left(-7\right) as a single fraction.
5=\frac{21}{7}+b
Multiply -3 and -7 to get 21.
5=3+b
Divide 21 by 7 to get 3.
3+b=5
Swap sides so that all variable terms are on the left hand side.
b=5-3
Subtract 3 from both sides.
b=2
Subtract 3 from 5 to get 2.
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