Question

find the curved surface area and the total surface area of a cone with radius 3.5 CM and height 12 CM?

pls answer me fast....!​

Answer 1

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${ l}^{2} = {r}^{2} + {h}^{2} \\ = {3.5}^{2} + {12}^{2} = 156.25 \\ l = 12.5cm$

total surface area of cone=

$\pi \: r \: (l + r) = \frac{22}{7} \times 3.5(12 + 12.5) \\ = 11(24.5) = 269.5 {cm}^{3}$

curved surface area of cone=

$\pi \: r \: l = \frac{22}{7} \times 3.5 \times 12.5 \\ = 137.5 {cm}^{2}$

hope it helps u......

Answer 2

Step-by-step explanation:

TSA of cone pie r (r+l)

but In above it is 12 I am confused