In a cone with a slant height of 7.5 feet, the slant height forms a 38 degree angle with the radius. Find the surface area and volume of the cone.
2007-08-17 08:00:43 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
using the law of sines, the radius is 4.6
h=5.9
volume is 1/3*pi*r^2*h, or 131 cu ft
surface area is 2/3*pi*r*h = 56.8 sq ft
2007-08-17 08:13:14 · answer #1 · answered by Anonymous · 0⤊ 0⤋
1) The straight height of the cone is 7.5 * sin(38)
2) radius of circle is 7.5 * cos(38)
3) Then use cone formula to get surface and volume
http://www.science.co.il/Formula.asp
2007-08-17 15:18:05 · answer #2 · answered by Anonymous · 0⤊ 0⤋
height= 7.5*sin38º =4.62 feet
radius = 7.5 cos 38 =5.91 feet
V 1/3 pi*5.91^2 * 4.62=53.8*pi cubic feet
S= pi*5.91^2 +pi*5.91*7.5 =pi*79.25 square feet
2007-08-17 15:18:59 · answer #3 · answered by santmann2002 7 · 0⤊ 0⤋