WarmUp

1
Warm-Up

• Find the lateral and total surface area of the
  cylinder to the left. Use p3.
• Lateral 450 in2
• Total 600 in2
• A hotel installs new carrels used for public
  telephones. The new carrels are half of a
  cylinder with an open top. How much material is
  needed to construct a new carrel? Use p3.
• Half the lateral half a base
• 1950 253.5 2203.5 in2

2
Surface Area of Pyramids

• Saturday, December 26, 2009

3
Surface Area of Pyramids

• Slant height (l) the height of the triangular
  sides
• Total Surface Area
• Area of the polygonal base and the triangular
  sides
• S (1/2)Pl B
• Lateral Surface Area
• Area of the triangular sides
• S (1/2)Pl

4
EX 1 Find the lateral total Surface Area

• Lateral Surface Area
• S (1/2)Pl
• S (1/2)(48)(10)
• S 24(10)
• S 240 in2

• Total Surface Area
• S (1/2)Pl B
• S (1/2)(48)(10) 122
• S 24(10) 144
• S 240 144
• S 384 in2

5
Example 2

• Find the surface area of a regular square pyramid
  with a slant height of 17m and a base perimeter
  of 44 m.

6
Example 3

• Find the length of the slant height of a square
  pyramid if one side of the base is 15 feet and
  the surface area is 765 ft .

2
7
Homework

• Wks 8.3 Surface Area of Pyramids and 6 and 9
  on the back of Wks 8.1 (Prisms)
• YOU MAY USE A CALCULATOR ON THE HOMEWORK
  TONIGHT!!
• QUIZ tomorrow over surface area of prisms,
  cylinders, pyramids (lateral and total). Please
  bring your formula card!