Solve for a
a=2b+7
Solve for b
b=\frac{a-7}{2}
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-a+b+19+b+0=12
Combine a and -2a to get -a.
-a+2b+19+0=12
Combine b and b to get 2b.
-a+2b+19=12
Add 19 and 0 to get 19.
-a+19=12-2b
Subtract 2b from both sides.
-a=12-2b-19
Subtract 19 from both sides.
-a=-7-2b
Subtract 19 from 12 to get -7.
-a=-2b-7
The equation is in standard form.
\frac{-a}{-1}=\frac{-2b-7}{-1}
Divide both sides by -1.
a=\frac{-2b-7}{-1}
Dividing by -1 undoes the multiplication by -1.
a=2b+7
Divide -7-2b by -1.
-a+b+19+b+0=12
Combine a and -2a to get -a.
-a+2b+19+0=12
Combine b and b to get 2b.
-a+2b+19=12
Add 19 and 0 to get 19.
2b+19=12+a
Add a to both sides.
2b=12+a-19
Subtract 19 from both sides.
2b=-7+a
Subtract 19 from 12 to get -7.
2b=a-7
The equation is in standard form.
\frac{2b}{2}=\frac{a-7}{2}
Divide both sides by 2.
b=\frac{a-7}{2}
Dividing by 2 undoes the multiplication by 2.
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