Solve for x_1, x_2
x_{1}=-\frac{c+4}{2a}
x_{2}=\frac{c}{2a}
a\neq 0
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2x_{2}=\frac{c}{a},x_{2}+x_{1}=-\frac{2}{a}
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.
2x_{2}=\frac{c}{a}
Pick one of the two equations which is more simple to solve for x_{2} by isolating x_{2} on the left hand side of the equal sign.
x_{2}=\frac{c}{2a}
Divide both sides by 2.
\frac{c}{2a}+x_{1}=-\frac{2}{a}
Substitute \frac{c}{2a} for x_{2} in the other equation, x_{2}+x_{1}=-\frac{2}{a}.
x_{1}=-\frac{c+4}{2a}
Subtract \frac{c}{2a} from both sides of the equation.
x_{2}=\frac{c}{2a},x_{1}=-\frac{c+4}{2a}
The system is now solved.
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