Answer:
4
Step-by-step explanation:
Each walk-in is $5, so 20 divided by 5 is 4. 4 classes.
Answer:
S = 128πx² + 64πx + 8π
Step-by-step explanation:
Suraface area of a cylinder is given by:
S = 2πrh + 2πr²
We know that the height is 3 times as big as the radius, hence:
h = 3r
so we can plug in the new h value and rewrite the S equation as:
S = 2πrh + 2πr²
S = 2πr(3r) + 2πr²
S = 6πr² + 2πr²
S = 8πr²
We're given in the question that the radius is (4x + 1) inches, so plug that into r.
Given: r = 4x + 1
Therefore,
S = 8πr²
S = 8π(4x + 1)²
S = 8π(16x²+8x+1)
S = 128πx² + 64πx + 8π