Question

-x + y = 4x + 3y = 4

Answer 1

The given equations are,

`\begin{gathered} -x+y=4 \\ x+3y=4 \end{gathered}`

Adding the first and second equations, we have,

`\begin{gathered} -x+y+x+3y=4+4 \\ 4y=8 \\ y=(8)/(4)=2 \end{gathered}`

Substituting the value of y in first equation, we have,

`\begin{gathered} -x+2=4 \\ -x=4-2 \\ x=-2 \end{gathered}`