00:01
Okay, so what we're assuming in this problem is that we have a wall and it's going to make a right angle with the ground and then a ladder coming from that wall.
00:10
So what we know is that this is five feet.
00:13
We also know that we have a 20 foot ladder, so that goes all the way across.
00:19
And then up this wall is 12 feet, is where this rung in the ladder is.
00:27
So what is really important is as i make similar triangles in here, i even tell you similar triangles that this piece right in here is 20 minus 12, so it's eight.
00:42
So as we set up proportions, they are proportional, i would write it out as the big side length to the small side length.
00:52
So that's 20 is corresponding to eight is equal to the big side length, which is five compared to x.
01:01
And either way, what i need to do is cross multiply...