Question 724873
<pre>
All points on the x-axis are like (2,0), (-4,0), (7,0), etc.
They all have their y-coordinates as 0.  x-intercepts are all
on the x-axis, so to find them, we let y=0.

All points on the y-axis are like (0,3), (0,-5), (0,6), etc.
They all have their x-coordinates as 0.  y-intercepts are all
on the y-axis, so to find them, we let x=0.

Edwin</pre>