\left\{ \begin{array} { l } { 2 \times 15 y = 242 } \\ { x + y = 9 } \end{array} \right.
Solve for y, x
x=\frac{14}{15}\approx 0.933333333
y = \frac{121}{15} = 8\frac{1}{15} \approx 8.066666667
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30y=242,y+x=9
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.
30y=242
Pick one of the two equations which is more simple to solve for y by isolating y on the left hand side of the equal sign.
y=\frac{121}{15}
Divide both sides by 30.
\frac{121}{15}+x=9
Substitute \frac{121}{15} for y in the other equation, y+x=9.
x=\frac{14}{15}
Subtract \frac{121}{15} from both sides of the equation.
y=\frac{121}{15},x=\frac{14}{15}
The system is now solved.
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