How to Graph Equations on One Set of Axes

Transcript

How to graph equations on one set of axes? I'm Bon Crowder and we're talking about graphing equations using the Cartesian coordinate plane. So, there's different tactics for graphing for various different kinds of equations. But one thing always works and that's to draw a T chart. And so, that's what we're going to do today. So, typically what I do is, I like to start with numbers that are central to the origin. So, I use negative two, negative one, zero, one and two. Those are always handy to start with, but sometimes you have to branch out to go things like negative 100 and 100 or smaller, like one-half and negative one half. So, depending on how much we can see in that little, tight domain there, is whether or not we're going to actually use these other crazy ones. So, we have a nice, little equation here, one of my favorites. And we're going to calculate the Y based on the X. So, we plug in the independent variable, negative two to our equation. Three times negative two is negative six, plus two is negative four. Then we plug in negative one. So that's negative three plus two is negative one. And then, we plug in zero. Now, you might notice that this is a linear equation, so we really only need two of these. But since we started out with all five of those, we're going to go ahead and crank them out. So this gives us five and then, three times two plus two is eight, I believe. Now, we have negative two, negative four, negative one, negative one, zero, two, one, five and two, eight. It looks like we have a pretty good idea what this graph looks like just using these. So, I'm not going to go to this crazy 100's and one halves and things like that. I'm Bon Crowder and that's how you can graph any equation.

Bon Crowder has taught math to over 15,000 adults in living rooms, classrooms and conferences.

×