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# Measuring angles with a circular protractor

## Video transcript

measure the angle in degrees so here we have this blue angle that we want to measure in degrees and it's sitting on top of this circle that circle is actually a protractor sometimes we see and maybe what you're used to seeing is protractors that are more semicircle shape something like this and those semicircle protractors measure from 0 to 180 degrees which is good but a circle is even better a full circles better because an angle can measure up to 360 degrees so a full circle allows us to measure an angle of any size instead of only an angle up to 180 degrees now the way we're going to measure this angle is the same way we would on a semicircle protractor the first thing we want to do is make sure one of our rays lines up to zero so here's one of our rays and it's lining up to zero on the protractor so that's nice it's already lined up for us and then we're going to measure the opening all the way to the other ray two right here and so if our angle only measured opened up this far it will be a 10 degree angle it's let's say it opened to here it would be a 50 degree angle but our angle measures all the way to here to the hundred sixty degrees so a hundred sixty degrees is the measure of our angle and again when you measure on a circle protractor or any protractor for that matter you're going to line one ray up to the zero and then measure the opening till you get to the other ray which in this case opened up to 160 degrees