Question

A
find the total surface area of a solid, right circular cone of height 4 cm and
Tadius 3 cm​

Answer 1

Answer:

A=75.4cm²

explaination:

using the formula,

$A = \pi \: rl + \pi \: {r}^{2}$

$l = \sqrt{ {r}^{2} } + {h}^{2}$

solving for A,

$A = \pi \: r \: (r + \sqrt{ {h}^{2} } + {r}^{2}$)

$= \pi.3.(3 + \sqrt{ {4}^{2} } \times {3}^{2}$ )

$= 75.39822{cm}^{2}$

A≈75.4cm²