\left\{ \begin{array} { l } { x = y + 2 } \\ { 9 y = 8 n - 2 } \end{array} \right.
Solve for x, y
x=\frac{8n+16}{9}
y=\frac{8n-2}{9}
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x-y=2
Consider the first equation. Subtract y from both sides.
9y=8n-2,-y+x=2
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.
9y=8n-2
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{8n-2}{9}
Divide both sides by 9.
-\frac{8n-2}{9}+x=2
Substitute \frac{-2+8n}{9} for y in the other equation, -y+x=2.
x=\frac{8n+16}{9}
Subtract \frac{2-8n}{9} from both sides of the equation.
y=\frac{8n-2}{9},x=\frac{8n+16}{9}
The system is now solved.
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