Solve for x
x=\frac{4-y}{9}
Solve for y
y=4-9x
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9x=4-y
Subtract y from both sides.
\frac{9x}{9}=\frac{4-y}{9}
Divide both sides by 9.
x=\frac{4-y}{9}
Dividing by 9 undoes the multiplication by 9.
y=4-9x
Subtract 9x from both sides.
Examples
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Matrix
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Simultaneous equation
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\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
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Limits
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