Question 43733
{{{3x+y=-1}}}
{{{9x+3y=-3}}}

Let's start with the first equation, getting it as a function of y:

{{{3x = -1 - y}}}
{{{3x + 1 = -y}}}
{{{-3x - 1 = y}}}

Second:

{{{9x + 3y = -3}}}
{{{9x + 3 = -3y}}}
{{{-9x - 3 = 3y}}}
{{{y = (-9x - 3)/3}}}
{{{y = -3x - 1}}}

Are you sure the equation is right? For any value of x, we can calculate -3x - 1 to get y. See the graph, any point in it is a solution:

{{{graph(600, 600, -6, 6, -10, 10, -3x - 1)}}}