The number without the variable (the letter x) is referred to as the y intercept. Therefore, it refers to the point along the y axis (up and down). For instance, in the first problem, the y intercept is -3. You would then go down 3 spaces and draw in the point.
The slope always has the x variable next to it. For instance, the slope of the first question is (positive) 2. To graph that, you would go up 2, and to the right one. Then you would repeat.