Answer:
r=2/3
Step-by-step explanation:
The formula for the lateral surface area of a right circular cone is:

where r is the radius of the base, and l is the slant height.
Plugging in the values we get:
The answer is 1 because 1×1=1
y = −1/4x^2 + 4x − 19
1. Use x = -b/2a to find x.
x = -4/2(-1/4)
x = -4/(-1/2)
x = -4/1 • (-2/1)
x = 8/1
x = 8
2. Plug x into the function to find your vertex.
Replace every x you see in the function with 8 and do the math.
Take it from here.