Question

the area of a circle varies directly as the square of its radius.When the radius is 7cm, the area of the circle is 154cm square.find the area of the circle whose radius is 14 cm.​

Answer 1

Answer:

616

Step-by-step explanation:

Answer 2

Given - Radius = 14 centimetres

Find - Area of circle with given radius.

Solution - As the question mentions, the area of a circle varies directly as the square of its radius. So, we can write A1/A2 = r1²/r2². In the formula, A1 is area of circle 1, R1 is radius of circle 1, A2 is area of circle 2 and R2 is radius circle 2.

Now, keeping the given values to find the area of circle.

154/A2 = 7²/14²

A2 = 154*14*14/7*7

A2 = 154*2*2

A2 = 616 square centimetre.

Thus, using the given fact, area of circle with radius 14 centimetres is 616 square centimetre.