00:01
This problem uses triangle properties and properties of angles to solve for the missing angles.
00:08
So first we will solve for angle a.
00:12
So if we view the largest triangle here, angle a is the only one missing.
00:19
So we'll subtract 40 and 71 from 180 to get 69 degrees.
00:25
So a is 69 degrees.
00:29
Then we'll solve for angle b.
00:30
Angle b is on a linear pair with 133, and so we can subtract from 180 to get that as well.
00:40
So 180 minus 133 is 47 degrees.
00:45
So i'm filling in as i go here because we've kind of got a lot going on.
00:51
So angle c is found using the exterior angle theorem, which just says that angle 69 and angle 47 are called remote interior angles.
01:02
Those are non -adjacent to the exterior angle.
01:06
Again, exterior angle is formed by extending one side of the triangle.
01:11
So 69 and 47 will add up to give me the same thing as angle c here...