00:01
Alright, so in this problem we want to find the length of rt.
00:04
We're told that pq is a mid -segment, and we have some measurements on this triangle right here.
00:11
And i'm going to tell you, we've got to be careful.
00:13
Okay, so here's the thing.
00:16
The mid -segment, so two times the mid -segment is going to equal the third side, or the side that it's not touching.
00:28
Oops.
00:29
Okay, so that's the property i'm going to use.
00:32
So if i double the x plus 9, it has to equal the 4x minus 27.
00:41
And then we do some math.
00:43
We distribute the two in.
00:46
2x plus 18 equals 4x minus 27.
00:51
We're going to subtract the 2x.
00:54
I'm going to add the 27.
00:56
So when i do that, these reduce out, but 18 and 27 combined is 45.
01:05
4x minus 2x is 2x, and the 27 and negative 27 reduce out.
01:16
So now when you divide by 2, you get 22 .5 is equal to x.
01:23
And you might think, there's my answer, but you look over to the left and none of those choices are there.
01:29
Remember, this is what x equals, and this is a very kind of a common trick on multiple choice tests, on standardized tests...