Answer:

Step-by-step explanation:
we know that
The lateral area of the cone is equal to

where
r is the radius of the base
l is the slant height
we have

Applying the Pythagoras Theorem find the slant height

substitute in the formula

Answer:
80
Step-by-step explanation:
89^2-39^2=6400, 6400=80^2
3,5 is the answer i belive
Answer:
6a + 15
Step-by-step explanation: