 Just as we've done for all of the other sections, we are going to fill in the missing coordinates for some trapezoids. So here we have trapezoid rock, and we are told that O up here, whoops, is the point AR. Well, what that tells us is that the distance from here to here is A, and the distance up is R. Well, when I see these marks, that means they're congruent, so I know that that is A, and I can then fill in RC and K, the ordered pairs. So, let's start with R. Since R is on the y-axis, we're just going straight up. That's the point 0A, and C, we're just going straight across on the x-axis, so that is the point A0, and K, obviously, is at 0, 0. In isosceles trapezoid O, R, C, H, we're given a couple of things. O is JA, so what you have to understand is that from here to here is J, and then up is A. We are also told that C is at S, so what you have to notice here is that this short distance here is J, and the whole distance is S. Well, because this is a trapezoid that's isosceles, what we know is that this piece right here has to be congruent. I can draw a congruent triangle on this side, and I know that this distance is also J, because those have to be congruent. So, in order to figure out these other ordered pairs, first I'm going to start with the easy one, which is H, I know that's at 0, 0, and the only other one that I need to figure out is R, and so the way you're going to figure out R is using this information that I know this little piece is J. So, to get to the R, what you would do is you would start at 0, 0, and you would stop here, and then go up. Well, because we're not going all the way out to S, we're not going the total distance of S, but what we're doing is stopping where this distance from this ordered pair to this one is J units. So what we're doing is we're actually going the whole distance of S and then backing up J units. So, the way that we would write that is S minus J, and then the distance that we go up is going to be congruent to this distance, so that would be A. In isosceles trapezoid BACH, we're doing a similar thing to what we did in the last problem. So, first I'm going to notice that from 0, 0 out to here is M units because that's the point M0, and the distance from 0, 0 to the left to get to point C is K units because that ordered pair is negative K0. So, what that tells us is I can draw a congruent triangle over here and know that if this is K, then let me change my color so you can see this, then this distance is also K. So what we're doing to get point B is we're going all the way out M units, but then we're backing up K units to get to here. So what we do is we say that the X value is M minus K, and then nowhere did it tell us how far it is to go up. So that's where we're going to make up a value. So it doesn't matter what letter you use, let's just say that that is what haven't we used. Let's say it's W, and so we're going to go up W. So then for point H, because that's on the Y axis, we're just going up W units. So that's the point 0 W.