Answer:

Step-by-step explanation:
The formula of a lateral area of a cone:

r - radius
l - slant height
The formula of a surface area of a cone:

We have r= 8in and l = 21in. Substitute:


I thinks is the first one
C = 2πr
17 = 2(3.14)(r)
17 = 2(3.14r)
17 = 6.28r
6.28 6.28
2.71 ≈ r
Answer: The 4 answers are x=18, x=3, x=48, x=81 1/2.
Step-by-step explanation: Isolate the variable by dividing by each side by factors that don't contain the variable.