How Do You Find the Radius of a Circle if You Know the Area?

Remember, to find the area of a circle, you need to multiply pi by the radius squared
The area, 'A', of the circle is 153.86 inches squared
'π' is pi, an irrational number with a value of approximately 3.14
'r' is the radius, which is what we are solving for here
We plugged our information into the A=πr² formula
We get "r=7", which means the radius of the circle is 7 inches!

1. Remember, to find the area of a circle, you need to multiply pi by the radius squared
2. A = πr²
1. Our formula: A = πr²
2. The area, 'A', of the circle is 153.86 inches squared
3. 'π' is pi, an irrational number with a value of approximately 3.14
4. 'r' is the radius, which is what we are solving for here
1. Our formula: A = πr²
2. The area, 'A', of the circle is 153.86 inches squared
3. 'π' is pi, an irrational number with a value of approximately 3.14
4. 'r' is the radius, which is what we are solving for here
5. Plugging in, we get:
6. 153.86 = (3.14)r²
1. Now our equation looks like this:
2. 153.86 = (3.14)r²
3. The goal is to isolate and solve for 'r', which is the radius
4. In order to do this, use the order of operations in reverse
5. So we divide both sides of the equation by 'π' in order to isolate 'r'
6. Then take the square root of both sides to get 'r' equals 7 inches squared

The area of the following circle is 153.86 in2. Find the radius of the circle. Use 3.14 for π.