How do you label points where the line crosses the axes?

Question

I am doing homework and this is the equation: y= -x -4 along with graph to chart it on. We are working on integer linear equations and graphing on charts. If you could help, it would clear some things up for me! Thanks, Clara 

Answer 1

Hi Clara,

You are asking how to label the points where the line crosses the axis, is that correct?

Like Andy answered you, your slope is -1, (or -1/1, rise over run) and your y-intercept is -4 (since y = mx + b).

Since you know that you have a point at (0,-4), you can then use your slope, -1, to find another point on your line for this equation. From the point (0,-4), you would move down one unit ( -1 "rise") and to the right 1 unit (positive 1 "run"), placing your next point at (1,-5). You mark both of these points with a very small circle or "dot" and connect the lines with a ruler, putting an arrow on each end since it goes on forever.

If this doesn't answer your question, please let me know and I will clarify!

Hope this helps!

Answer 2

The equation we are working with is y = -x - 4

This equation is in slope-intercept form (y = mx + b), and m = -1 and b = -4. This means that the slope is -1 and that the y-intercept is -4. Thus, we know that the line is downward sloping, which means that it looks more like a backslash (\) than a forward slash (/). Also the y intercept is the point where the line intersects the y-axis. Thus, we know that the line intersects the y-axis at -4. In other words, the line travels through the point (0,-4).