Solve for x, y
y=-\frac{9}{P}
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y+3x=0
Consider the second equation. Add 3x to both sides.
Px=3,3x+y=0
To solve a pair of equations using substitution, first solve one of the equations for one of the variables. Then substitute the result for that variable in the other equation.
Px=3
Pick one of the two equations which is more simple to solve for x by isolating x on the left hand side of the equal sign.
x=\frac{3}{P}
Divide both sides by P.
3\times \frac{3}{P}+y=0
Substitute \frac{3}{P} for x in the other equation, 3x+y=0.
\frac{9}{P}+y=0
Multiply 3 times \frac{3}{P}.
y=-\frac{9}{P}
Subtract \frac{9}{P} from both sides of the equation.
x=\frac{3}{P},y=-\frac{9}{P}
The system is now solved.
Examples
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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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