Solve for a
a=-\frac{b}{2}
Solve for b
b=-2a
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-2a=b
Swap sides so that all variable terms are on the left hand side.
\frac{-2a}{-2}=\frac{b}{-2}
Divide both sides by -2.
a=\frac{b}{-2}
Dividing by -2 undoes the multiplication by -2.
a=-\frac{b}{2}
Divide b by -2.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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y = 3x + 4
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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 ) }
Integration
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Limits
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