So the line will look something like that. So let me, oops, though I was using the tool that would draw a straight line. Points, two points are enough to graph a line, we can now graph it. And so, we could plot that point as well. And let's see, what is that equal to? That is equal to, let's see, they're both divisible by eight, so that's nine over two. So we could say, alrightġ6Y is equal to 72. And so we could solve, we could solve that. Now what about the y-intercept? Well, we said X equals We're referring to the point where the line actually So the point, let's see, Y is zero, X is one, two, three, four, five, six, seven, eight. You just have to say hey, nine times X is 72, X would be eight. So if nine times X is 72, 72 divided by nine is eight. So when Y is zero, what is X? So when Y is zero, 16 times zero is zero, that term disappears, and you're left with 9X is equal to 72. And the y-intercept is going to happen when X is equal to zero. So how do we do that? Well to figure out the x and y-intercepts, let's just set up a little table here, X comma Y, and so the x-intercept is going to happen when Y is equal to zero. So easy to figure out from these other forms right over here. Y-intercept pretty clearly from standard form and the x-intercept. So the thing that standardįorm is really good for is figuring out, not just the y-intercept, y-intercept is pretty good if you're using slope-intercept form, but we can find out the So let's say I have the linear equation, it's in standard form, 9X plus 16Y is equal to 72. And what I want to do in this video, like we've done in the ones on point-slope and slope-intercept is get an appreciation for what is standard form good at and what is standard form less good at? So let's give a tangible example here. And standard form takes the shape of AX plus BY is equal to C, where A, B, and C are integers. To get into in this video is another form. This is point-slope formĪnd we do videos on that. And if you know that X equals, X equals A, Y equals B, satisfies that equation, then in point-slope form youĬan express the equation as Y minus B is equal to M times X minus A. Solutions of that equation has a slope M. If you know that some, if you know that there'sĪn equation where the line that represents the You can algebraically manipulateįrom one to the other. And these are just different ways of writing the same equations. We've also seen that you can also express things in point-slope form. Represents the XY pairs that satisfy this equation, it would intersect the y-axis at the point X equals zero, Y is equal to B. And then from B you're able to figure out the y-intercept. This MX term right over here and M would represent the slope. Of Y is equal to MX plus B, where M and B are constants. Slope-intercept form, where it would be of the form Note: Not all browsers show the +1 button.Looked at several ways of writing linear equations. Logging in registers your "vote" with Google. (If you are not logged into your Google account (ex., gMail, Docs), a login window opens when you click on +1. Note: If a +1 button is dark blue, you have already +1'd it. If you like this Page, please click that +1 button, too. If you like this Site about Solving Math Problems, please let Google know by clicking the +1 button.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |