Solve for x
x=45-4y
Solve for y
y=\frac{45-x}{4}
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x+y+3y=45
Multiply both sides of the equation by 3.
x+4y=45
Combine y and 3y to get 4y.
x=45-4y
Subtract 4y from both sides.
x+y+3y=45
Multiply both sides of the equation by 3.
x+4y=45
Combine y and 3y to get 4y.
4y=45-x
Subtract x from both sides.
\frac{4y}{4}=\frac{45-x}{4}
Divide both sides by 4.
y=\frac{45-x}{4}
Dividing by 4 undoes the multiplication by 4.
Examples
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Matrix
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Simultaneous equation
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Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
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Limits
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