00:01
So in this problem, we're trying to show that the quadrilateral is going to be a parallelogram.
00:06
So the first thing that i'm going to do is i'm going to just sketch the graph so you can see what this looks like.
00:13
So i have my first point at 1 .3.
00:23
My second point is at negative 2 .5, 2.
00:30
The next point is at negative 3 .5, 4.
00:40
And the final point is at positive 2.
00:45
And so what we want to show is that this is, in fact, a parallelogram.
00:49
So if i find the slopes of each of the two lines, and i show that opposite sides have equal slopes, then we'll have a parallelogram.
00:59
So in this particular case, right, if i'm taking the point, negative 3 .5 and 4, which is this point right here, and the point 1, 3, the slope will equal the changes of the ys over the changes of the xes.
01:25
So the ys go from 4 to 3, which is down 1, and the xes go from negative 3 .5 to positive 1, which is up 4 .5, which is equal to negative 10 over 45, which is equal to 2 .9s.
01:49
So this side here has a slope of negative 2 .9s.
01:54
So if this side over here has a slope of negative 2 .9th, then those two sides would be parallel...