Lesson video

Hello! My name is Mr. Clasper, and today we are going to be constructing an angle bisector.

Going to construct an angle bisector.

To do this, we need a compass.

We're going to make a mark on both of the line segments without changing the distance of the compass.

Once we've done this, we can then move our compass so that the point lies on the intersection between the mark that we just made and one of the line segments.

I'm going to make a curve.

I'm then going to repeat the process using the other mark I made earlier.

Our angle bisector will be a line segment from the point where our two original line segments met and the intersection of the two curves that we've just created.

We've now bisected the angle given.

This means that the two angles we've now created are equal.

Here's a question for you to try.

Pause the video to complete your task, and click resume once you're finished.

And here is the solution.

So this is what your diagram should look like.

If you've drawn one yourself, just make sure you've drawn an 80-degree angle.

And once you've drawn your bisector, you should find that you've created two 40-degree angles.

And here is your last question.

Pause the video to complete your task, and click resume once you're finished.

And this is what your solution should look like.

So if you've got a 120-degree angle, once you've drawn your bisector, you should find that you've created two 60-degree angles.

And that is the end of our lesson on constructing angle bisectors.

Why not give the exit quiz a go? I'll hopefully see you soon.