The function f(r) gives the area of a circle with radius r. It can be written in equation form as f(r) = 3.14r2. What is f(5)?

A. 28.14
B. 31.40
C. 246.49
D. 78.50

Respuesta :

f(r) = 3.14r^2....and ur looking for f(5)....so basically all u do is sub in 5 for r.

f(5) = 3.14 * 5^2
f(5) = 3.14 * 25
f(5) = 78.50 <===


Answer:

D. 78.50

Step-by-step explanation:

apex.