The height of a cone is 21 cm. Find the area of the base if the slant height is 28 cm.
Given,
Height of cone (h) = 21 cm
Slant height ( l )=28 cm
∴l2=r2 + h2 =r =
= 
=7√7 cm
∴ Area of the base = πr2=
×
cm2 = 1078 cm2
4
The height of a cone is 21 cm. Find the area of the base if the slant height is 28 cm.
Given,
Height of cone (h) = 21 cm
Slant height ( l )=28 cm
∴l2=r2 + h2 =r == =7√7 cm
∴ Area of the base = πr2=×cm2 = 1078 cm2