Let's just start with x=20 and then do some algebra to it to make it all complicated
x = 20
2 * x = 2 * 20
2x = 40
2x - 13 = 40 - 13
2x - 13 = 27
Answer:
Step-by-step explanation:
Remark
The measurement of the arc is 3Pi
that represents 108 / 360 of the circle.
Equation
108/350 2 * pi * R = 3* pi
Solution
Pi is on both sides of the equation. They both cancel.
108/360 = 0.3
0.3 * 2 * R = 3
0.6 * R = 3
R = 3/0.6
R = 5
To find the circumference of a circle you have to multiple the radius by 2 and also by pi. So, to find the radius when given just the circumference, who have to do the reverse operation and divide the circumference by 2 and also by pi to get the answer of 22.92993631, which you could of course round.
