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11.4 Areas of regular polygons. Central Angle Angle formed from center of polygon to consecutive vertices. Radius. Apothem Distance from center of polygon to side. Things to notice, all parts can be found using SOHCAHTOA. It is isosceles, so you can break up the triangle in half.
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11.4 Areas of regular polygons. Central Angle Angle formed from center of polygon to consecutive vertices. Radius Apothem Distance from center of polygon to side. Things to notice, all parts can be found using SOHCAHTOA. It is isosceles, so you can break up the triangle in half.
The area of these 5 triangles is = Or we can think of it as What do you think we can do to find the area of this shape? So you see it’s
Let’s find the area of a pentagon with side length 10 Which trig function do we use to find the apothem? 72o TANGENT! Plug in, be careful with the perimeter! 36o 5 10
R - HW #31: Pg 431: 4—10 even; Pg 443: 1—11 odd, 13—16 all • Quiz Monday • I can give you a rough grade estimate at break or lunch.