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Interpreting angles

8 videos
6 skills
Now that we know what angles are, let's dig a bit deeper and classify them and understand their properties better. Acute, obtuse, right, adjacent--all are angles that we will be become familiar with. We'll all also examine how intersecting lines play a role. Lots of great stuff in this tutorial, so pull up a chair and get your angle on! Common Core Standards: 4.MD.C.7, 4.G.A.1

Acute right and obtuse angles

VIDEO 5:32 minutes
We briefly discussed the types of angles in the last tutorial but we'll delve a little deeper into acute, obtuse, and right angles here.

Measuring angles in degrees

VIDEO 8:22 minutes
Let's come up with an exact way to measure an angle using a protractor. We'll also learn about acute angles. Not to be confused with augly angles :)

Angle types


Recognizing angles

VIDEO 2:15 minutes
Let's do a few example exercises in which you recognize and identify the type of given angle. This is a lot of fun!

Recognizing angles


Drawing acute, right and obtuse angles

VIDEO 2:40 minutes
These 3 types of angles will often come up in your geometry studies. Let's make sure you know how to draw an acute, obtuse, and right angle.

Identify the angle example

VIDEO 2:03 minutes
We're matching the visual angle with the corresponding angle measure. Great practice. See if you do it on your own before listening to Sal!

Benchmark angles


Parallel and perpendicular lines intro

VIDEO 2:08 minutes
Do the two lines intersect or stay apart? If they intersect, do they do so thereby creating a 90 degree angle? These are the kinds of questions we ask ourselves when we learn about parallel and perpendicular lines.

Identifying parallel and perpendicular lines

VIDEO 3:35 minutes
Let's now apply what we learned and do an exercise together in which we identify parallel and perpendicular lines.This is great practice.

Solving for an angle

VIDEO 1:43 minutes
Let's use a little math with our geometry and see if we can solve for a mystery angle. In this example we know the adjacent angle AND the combination of the mystery angle and the adjacent angle. Mystery angle...how big are you?

Decomposing angles