Question

please answer me fast correct p​

Answer 1

Step-by-step explanation:

Given:- Slant height (l) of a cone =13 cm.

Height (h) of a cone = 12 cm.

$radius \: of \: \: a \: cone \: = \sqrt{( {l)}^{2} - ( {h)}^{2} }$

$= \sqrt{( {13)}^{2} - ( {12)}^{2} } \: \: cm$

$= \sqrt{169 - 144} \: \: cm$

$= \sqrt{25} \: \: \: cm$

$= 5 \: \: \: cm$

Radius of a cone is 5 cm.

Curved Surface area of a cone = π r l sq. unit

$= \frac{22}{7} \times 5 \times 13 \: \: sq.cm \: \: (\pi = \frac{22}{7} )$

$= \frac{1430}{7} \: \: \: sq.cm$

$= 204.2857 .. \: \: \: sq.cm$

Answer:- Curved surface area of a cone is 204.28..

Answer 2

given

l=13

h=12

r=?

by Pythagoras theorem

ab^2=ac^2+bc^2

ab=13, ac=12, bc=?

ab^2-ac^2=bc^2

169-144=bc^2

25=bc^2

√25=bc

bc=5

Now,CSA of cone=πrl

r=5,l=13

=>3.1415X13X5=

204.1975cm^2