\{ 42 x + 20 y = 940
Solve for x
x=\frac{470-10y}{21}
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42x=940-20y
Subtract 20y from both sides.
\frac{42x}{42}=\frac{940-20y}{42}
Divide both sides by 42.
x=\frac{940-20y}{42}
Dividing by 42 undoes the multiplication by 42.
x=\frac{470-10y}{21}
Divide 940-20y by 42.
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