\{ 3 x + 9 y = 18
Solve for x
x=6-3y
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3x=18-9y
Subtract 9y from both sides.
\frac{3x}{3}=\frac{18-9y}{3}
Divide both sides by 3.
x=\frac{18-9y}{3}
Dividing by 3 undoes the multiplication by 3.
x=6-3y
Divide 18-9y by 3.
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