Question

Please check :
A cone of height 8 cm has a curved surface area of 188.4 cm^2.Find its radius.
Take pi as 3.14

Answer 1

\[\pi*rl = 188.4\]
\[rl = 188.4/\pi = 188.4/3.14 = 60\]
Since, \[l = \sqrt{r^2 + h^2}\]
\[r\sqrt{r^2 + h^2} = 60\]

On squaring both sides

\[r^2(r^2 + 64) = 3600\]

\[r^4 +64r^2 - 3600 = 0\]

Answer 2

r^2 = 36 cm

Therefore r = 6 cm

Answer 3

steps are right...