Using a Protractor
Date: 8/15/96 at 18:27:35 From: Anonymous Subject: Using a Protractor How do I measure angles using a protractor? My protractor has two sets of numbers, one above the other. How do I know which set to use?
Date: 8/30/96 at 17:2:53 From: Doctor James Subject: Re: Using a Protractor Since you can measure angles from either side of the protractor, they have given you two sets of numbers. One set of numbers measures from the left side, the other measures from the right side. The way to figure out which to use is this: Put the bottom marking (where it will say either 0 or 180) on one leg of the angle, such that the other leg of the angle is going through the curved part of the protractor. So now you will know that the angle is one of the two angles it tells you. However, one of the two sets will tell you that the first leg is at 0 degrees; this is the set you want. You can check it because as the two legs get closer together, the angle should get smaller. -Doctor James, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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