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To review, comment below what the angles in a triangle add up to.

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In Geogebra, create a polygon with 4 sides (a quadrilateral). Click the Angle Measure tool and click the inside of your quadrilateral to measure the interior angles. Add up the angle measures. Then, take a screenshot of your quadrilateral and post it below along with the number you got from adding up the angles.

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In Geogebra, create a polygon with 5 sides (a pentagon). Click the Angle Measure tool and click the inside of your pentagon to measure the interior angles. Add up the angle measures. Then, take a screenshot of your pentagon and post it below along with the number you got from adding up the angles.

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In Geogebra, create a polygon with 6 sides (a hexagon). Click the Angle Measure tool and click the inside of your hexagon to measure the interior angles. Add up the angle measures. Then, take a screenshot of your hexagon and post it below along with the number you got from adding up the angles.

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As shown in the picture above, create 2 lines in Geogebra and connect them with a point where they intersect. Then, measure each of the 4 angles created by the lines. What do you notice about angles which are across from each other (such as angle AED and angle BEC above)? Post your results below.

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How many degrees are in a full circle? Post your answer below.

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Complementary Angles are angles which add up to 90°. Post an example of complementary angles below.

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Supplementary Angles are angles which add up to 180°. Post an example of supplementary angles below.

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Using the information from the previous 4 sections, can you write a formula for the sum of the angles in a polygon with "n" sides? Post it below.

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45° and 45°

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THE ANGLES ACROSS EACH OTHER ARE THE SAME

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THE ANGLES ACROSS EACH OTHER ARE THE SAME

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360

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360.1°

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Proof that vertically opposite angles are equal.

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Proof that vertically opposite angles are equal.

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Suppose the point where the lines intersect  is O.
So,
<AOD+<AOC=180˚
<BOD+<AOD=180˚
So,
<AOD+<AOC=<BOD+<AOD
<AOC-<BOD=<AOD-<AOD
<AOC-<BOD=0
<AOC=<BOD

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540

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720