How to find the surface area of a Cone
The video works the problem Surface Area of a Cone
In order to find the surface area of a cone you add the lateral area plus the base area
The lateral area of a cone equals 1/2 dπ*s
D = diameter
S = slant height
Base Area = πr^2
Find the surface area of a cone with a diameter of 6 units and a height of 4 units.
Step 1. The radius = ½ diameter = 3 units
Step 2 Find the slant height by using the Pythagorean Theorem a^2+b^2=c^2
Use the height and radius to find the slant height 3^2+4^2=c^2 which equals 9 +16 = 25
√25=5 equals your slant height
Step 3 Now use 1/2 dπ*s
1/2 6π*5=3π*5=15π which will equals the lateral area
Step 4. Find the base area by using πr^2
π3^2 = π9
Step 5 Add the lateral and base area in order to get surface area
15π+9 π=24π units^2
Check out the Video if confused Surface Area of a Cone
