Question

what is the total surface area of the cone of height 4 cm and radius 3 cm?

Answer 1

The formula for the total surface area of a rightcone is T.S.A=πrl+πr2 .

slant height ² = 3²+4²

l²=25

l=5cm

then the total surface area of cone

→ π(3)(5)+π(3)²

→15π+9π

→24π cm²

I hope this will help u :)

Answer 2

the formula to find total surface area of cone is 
πr(r+l)
to find l use l²=r²+h²

∴l²=3²+4²
     =9+16
     =25
∴l=5cm

now using πr(r+l)
                 3.14 *3(3+5)
                  3.14 *3(8)
                 9.42*8
                 75.36cm²