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What is an angle and how do we label, measure and construct them? Great question. Luckily we have all your answers! To begin our journey towards understanding angles, we'll learn terms like vertex, acute, obtuse, circle arc, circumference, and protractor. These basic angle concepts will get you on the road to angle domination! Common Core Standards: 4.MD.C.5, 4.MD.C.5a, 4.MD.C.5b, 4.MD.C.6, 4.MD.C.7, 4.G.A.1
The naming of an angle is related to the line segments that create it. We'll also learn about the angle's vertex. Come on. Let's do this.
Here's an example exercise in which we find the correct angle name(s).
Name angles by their vertex, endpoints, or labels.
Did you know that the measurement of an angle is realted to the arc of a circle? Yes, indeed! Watch.
We're slowly starting to put things together in this example exercise: angle, circle, circumference, and fractions. Woohoo!
Estimate and compare angle measures in situations.
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 :)
Let's use our virtual protractor to measure some angles together, shall we?
We're practicing measuring angles using the virtual protractor. Do this a few times with us and you'll use a real protractor like a pro!
Measure angles using a protractor.
As opposed to measuring an angle using a protractor, in this example we're constructing an angle. Same idea here, just a slightly different application. You got this.
Use a protractor to construct angles.