Solve for a
a=\frac{9b}{4}+7
Solve for b
b=\frac{4\left(a-7\right)}{9}
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-4a=-28-9b
Subtract 9b from both sides.
-4a=-9b-28
The equation is in standard form.
\frac{-4a}{-4}=\frac{-9b-28}{-4}
Divide both sides by -4.
a=\frac{-9b-28}{-4}
Dividing by -4 undoes the multiplication by -4.
a=\frac{9b}{4}+7
Divide -28-9b by -4.
9b=-28+4a
Add 4a to both sides.
9b=4a-28
The equation is in standard form.
\frac{9b}{9}=\frac{4a-28}{9}
Divide both sides by 9.
b=\frac{4a-28}{9}
Dividing by 9 undoes the multiplication by 9.
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