Welcome back to school! We needed some time to review geometry concepts, so we began with discussing how to measure the interior angles of a triangle. Using a protractor can be tricky, but just remember that the two sides of the angle being measured must cross the protractor. The vertex (or point) of the angle should be in the middle of the small circle at the bottom of the protractor. One side should intersect at 0 degrees and the location the second side intersects the protractor will be the measurement........but hold on! You say there are two numbers on the protractor where the second side intersects?! You would be correct, so you have to choose wisely. If the angle is an acute angle (smaller than the corner of your paper, or 90 degrees), then use the smaller number. If the angles is an obtuse angle (larger than the corner of your paper, or 90 degrees), then use the larger number. If you add up all the measurements (three angles total), then you will surely get a sum of 180 degrees. All interior angles of a triangle add up to 180 degrees. And since a quadrilateral (four-sided figure) is made of two triangles, the interior angles add up to 360 degrees. How many triangles make up a pentagon? Three. So that means that the interior angles of a pentagon add up to 540 degrees if each of the three triangles are 180 degrees. 180 x 30 =540.
To "Create These Figures", you are given the measurement of two or three angles in a polygon. Your job is to find the measurement of the missing angles and use a protractor to draw these figures. Remember, a reflex angle is an angle that measures more than 180 degrees. I have done number 1 for you. Please study the example and use this information to complete the homework. Have fun!
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