Remark
The first thing you should do is get a graph for this, so you can actually see what is going on. Then solve for slope y intercept. I put the graph into Desmos without a solution expression for y.
Graph Solution
The graph 3x - y + 1 = 0 shows you were the y intercept is. You can use this graph to draw your own along with a table.
Find slope y intercept form
3x - y + 1 = 0 Add y to both sides.
3x - y + y + 1 = y
y = 3x + 1
Answer
m is always the number in front of x when written in the slope intercept form.
