Question

How do you work this question out at the bottom? please help?????

Answer 1

Surface area of the cone:

Answer: l=20 cm.

Answer 2

Question Q1:
Surface area of the cone:

`\pi r l + \pi r^(2)=125 \pi /: \pi rl+ r^(2)=125 5l+ 5^(2)=125 5l+25=125 5l=100 l=100:5=20`
Answer: l=20 cm.