Given a circle with the area of 314in2. Find the radius of the circle. Take π as 3.14.
The picture below shows the circle with the radius r.
To find the radius of a circle, we can start with the formula for the area of a circle:
Since the value of the area is given as 314 in2, we can substitute A with 314. Similarly, we can substitute π with 3.14. These are shown below:
Now, we have 3.14r2 = 314. To get closer in finding r, we need to remove 3.14. To do so, we divide both sides of the equation with 3.14 as shown below:
Now, we have r2 = 100. Since r square is a multiplication of r two times, we can find r by taking the square root of 100. This is shown below:
Now, the calculated number 10, has no meaning unless we include the unit for it. Since the area is in in2, r will be in inch. Hence:
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