Solve for a
a=-\frac{x}{4}+10
Solve for x
x=40-4a
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8a=80-2x
Subtract 2x from both sides.
\frac{8a}{8}=\frac{80-2x}{8}
Divide both sides by 8.
a=\frac{80-2x}{8}
Dividing by 8 undoes the multiplication by 8.
a=-\frac{x}{4}+10
Divide 80-2x by 8.
2x=80-8a
Subtract 8a from both sides.
\frac{2x}{2}=\frac{80-8a}{2}
Divide both sides by 2.
x=\frac{80-8a}{2}
Dividing by 2 undoes the multiplication by 2.
x=40-4a
Divide 80-8a by 2.
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