Question

The function f(r) gives the area of a circle with radius r it can be written in equation form f(r)=3.14r^2 what is f(4)

Answer 1

Answer:

$f(4)=50.24$

Step-by-step explanation:

We are given the function representing the area of a circle as,

$f(r)=3.14r^2$, where 'r' is the radius of the circle.

It is required to find f(4).

So, we have,

$f(r)=3.14r^2$

implies $f(4)=3.14\times 4^2$

implies $f(4)=3.14\times 16$

implies $f(4)=50.24$

Thus, the value of f(4) is 50.24.

Answer 2

The value of $f(4)$ is 50.24

Explanation

The area of a circle with radius $r$ is given as:  $f(r)=3.14r^2$

Now, $f(4)$ means the value of $f(r)$ when $r=4$. So, we will just plug $r=4$ into both sides of the above function.

$f(4)= 3.14(4)^2\\ \\ f(4)= 3.14\times 16 =50.24$

Thus, the value of $f(4)$ is 50.24