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12.3 Surface Area of a Pyramids and Cones. Slant Height ( l ). Definition of a Regular Pyramids. A regular pyramid is a pyramid whose base is a regular polygon and whose vertex forms a segment with the center of the polygon perpendicular to its plane. Part of a Pyramid.
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12.3 Surface Area of a Pyramids and Cones Slant Height ( l )
Definition of a Regular Pyramids A regular pyramid is a pyramid whose base is a regular polygon and whose vertex forms a segment with the center of the polygon perpendicular to its plane.
Part of a Pyramid h is Height from base to vertex l is Slant height, The height of the triangle
Theorem Surface Area of a Regular Pyramid B is for base Area P is for perimeter l is for Slant height
Surface Area of a Regular Pyramid Let r = 3; h = 4 Find the Perimeter r is half the base edge
Surface Area of a Regular Pyramid Let r = 3; h = 4 Find the Perimeter r is half the base edge Base edge is 2(3) = 6 Square perimeter 4(6) = 24 P = 24
Surface Area of a Regular Pyramid Let r = 3; h = 4 ; P = 24 Find the Base Area
Surface Area of a Regular Pyramid Let r = 3; h = 4 ; P = 24 ; B = 36 Find the Base Area Base edge is 6 Base Area = (6)2 B = 36
Surface Area of a Regular Pyramid Let r = 3; h = 4 ; P = 24 ; B = 36 Find the Slant Height l Right Triangle
Surface Area of a Regular Pyramid Let r = 3; h = 4 ; P = 24 ; B = 36 ; l = 5 Find the Slant Height l Right Triangle side legs 3 and 4 32 + 42 = l 2 9 + 16 = 25 = l 2 l = 5
Surface Area of a Regular Pyramid Let r = 3; h = 4 ; P = 24 ; B = 36 ; l = 5
Surface Area of a Regular Pyramid Let r = 4; h = ; P = 24 ; B = ; l = 9 Find the Base and Perimeter
Surface Area of a Regular Pyramid Let r = 4; h = ; P = 24 ; B = ; l = 9 Find the Base and Perimeter
Surface Area of a Regular Pyramid Let r = 4; h = ; P = 24 ; B = ; l = 9 Find the Surface Area
Surface Area of a Regular Pyramid Let r = 4; h = ; P = 24 ; B = ; l = 9 Find the Surface Area
Surface of a Cone Finding the Base is Easier, since it is a circle.
Surface of a Cone Finding the Surface Area. r = 5, h = 12
Surface of a Cone Finding the Surface Area. r = 5, h = 12; need l
Surface of a Cone Finding the Surface Area. r = 5, h = 12; need l
Surface of a Cone Finding the Surface Area. r = 5, h = 12; need l
Homework Page 738-741 # 15 – 43 odd
Homework Page 738-741 # 14 - 38 even, 44 - 46