Question

$$\left. \begin{array} { l } { \{ \begin{array} { l } { x - 2 y = 9 } \\ { 2 x - 4 y = 18 } \end{array} } \\ { \{ \begin{array} { l } { 8 x + 2 y = 7 } \\ { y = - 4 y + 1 } \end{array} } \end{array} \right.$$

Answer

No Solution

Solution


Solve for \(y\) in \(y=-4y+14.\).
\[y=\frac{14.}{5}\]
Substitute \(y=\frac{14.}{5}\) into \(x-2y=9\).
\[x-\frac{2\times 14.}{5}=9\]
Substitute \(y=\frac{14.}{5}\) into \(2x-4y=18\).
\[2x-\frac{4\times 14.}{5}=18\]
Substitute \(y=\frac{14.}{5}\) into \(8x+2y=7\).
\[8x+\frac{2\times 14.}{5}=7\]
Solve for \(x\) in \(x-\frac{2\times 14.}{5}=9\).
\[x=9+\frac{2\times 14.}{5}\]
Substitute \(x=9+\frac{2\times 14.}{5}\) into \(2x-\frac{4\times 14.}{5}=18\).
\[18+\frac{4\times 14.}{5}-\frac{4\times 14.}{5}=18\]
Since \(18+\frac{4\times 14.}{5}-\frac{4\times 14.}{5}=18\) is not true, this is an inconsistent system.
No Solution