Answer:
90π cm²
Step-by-step explanation:
Given: Radius of circular base= 5 cm
height= 12 cm
Now finding the surface of cone.
Formula; Surface area of cone= [tex]\pi rl+ B[/tex]
Where; r= radius
l= slant height
B is the area of base, which is circle.
Area of circle (B)= πr²
Area of circle (B)= [tex]\pi \times 5^{2} = 25\pi[/tex]
∴ Area of circle (B)= [tex]25\pi[/tex]
Finding slant height (l)
Formula; [tex]l= \sqrt{r^{2}+h^{2} }[/tex]
⇒l = [tex]\sqrt{5^{2}+12^{2} } = \sqrt{25+144 }[/tex]
∴ l= [tex]\sqrt{169} = 13\ cm[/tex]
Next, using the formula for finding surface area of cone.
Surface area of cone= [tex]5\times 13\times \pi + 25\pi[/tex]
⇒ Surface area of cone= [tex]65\pi +25\pi = 90\pi[/tex]
∴ Surface area of cone= 90π cm²
Answer:
S.A. = 90 pi cm2
Step-by-step explanation:
1. pi(3.14) x radius(5) x slant height(13) = 90
