* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download UNIT VII
Survey
Document related concepts
System of polynomial equations wikipedia , lookup
Algebraic geometry wikipedia , lookup
Pythagorean theorem wikipedia , lookup
Rational trigonometry wikipedia , lookup
Line (geometry) wikipedia , lookup
History of trigonometry wikipedia , lookup
Integer triangle wikipedia , lookup
History of geometry wikipedia , lookup
Euclidean geometry wikipedia , lookup
Approximations of π wikipedia , lookup
Tessellation wikipedia , lookup
Compass-and-straightedge construction wikipedia , lookup
Area of a circle wikipedia , lookup
Transcript
Geometry Section 11.2 Notes NMV Areas of Regular Polygons Recall that a regular polygon is __a polygon that has bot equal sides and equal angles______________. The center of a regular polygon is ___a point in the center that is equidistant from each vertices______ A radius of a regular polygon is __a segment joining the center and a vertex_________________. An apothem of a regular polygon is __a segment from the center of the polygon perpendicular to the opposite side of the polygon______. An apothem also ___bisects_____ the side of a regular polygon. Draw an apothem in each of the diagrams below: The area of any regular n-gon can be found by dividing the regular polygon into n congruent triangles. This is done by drawing the radii of the regular polygon. A reg polygon = area of 1 triangle times the number of triangles = ___n__ ___________ = ________________ = ______________ So the formula for the area of a regular polygon is A regular polygon = _______________ Section 11.2 page 2 Notes NMV Examples: Find the (exact) area of each regular polygon. 12 12cm 8 in. Round to the nearest 1000th. Geometry Section 11.2 HW NMV Problems 3 & 7 involve trigonometry. Round to the nearest 1000th. 1. The stop sign at the right is a regular octagon. Its perimeter is 80 inches and its height is 24 inches. Find the apothem __________, radius __________ and area __________ of the stop sign. STOP Find the area of each of the regular polygons. 2. 3. 4 5. 4. 6cm m 6. 12in 7. A decagon with sides of length 26 in. 10 10 3 6cm m