The circumference of a circle is directly proportional to the length of its radius, while the area it encloses is directly proportional to the square of the length of its radius. if the area of a circle is multiplied by 49, then its circumference is multiplied by

If the area of a circle is multiplied by 49, then its circumference is multiplied by 7.

Step-by-step explanation:

Let r represent radius of circle.

We have been given that the circumference of a circle is directly proportional to the length of its radius.

, where,

C = Circumference of circle,

r = Radius.

We are also told that the area it encloses is directly proportional to the square of the length of its radius.

, where A represents area of circle and r represents radius.

is constant of proportionality in both formulas.

We are also told that the area it encloses is directly proportional to the square of the length of its radius. We can represent this information as:

The radius of circle would be square root of 49.

Since radius of circle is 7, therefore, its circumference is multiplied by 7.

-6 is the correct option from the above given options