Question

the total surface area of a cone is 704 square cm and radius of its base is 7cm find the slant height of the cone (pai)=22/7​

Answer 1

Given that,

The total surface area of a cone is 704 square cm

Radius of its base is 7 cm

To find,

The slant height of the cone.

Solution,

The formula of the total surface area of the cone is given by :

$A=\pi rl +\pi r^2$

l is slant height of the cone

$704=\dfrac{22}{7}\times 7l +\dfrac{22}{7}\times 7^2\\\\704=\dfrac{22}{7}\times 7l+154\\\\550=\dfrac{22}{7}\times 7l\\\\l=\dfrac{550}{22}\\\\l=25\ cm$

So, the slant height of the cone is 25 cm.