Hello, the below equation, and simplification of the equation, is offered in my study text. What I would love to know, is what rule allows me to isolate the variable "R" on one side of the equation. Maybe if someone recognized what type of equation this is, I could look it up and read about it, to get the understanding that I'd like. It is an engineering study, which assumes I would already have the mathematical knowledge.
2° / 360 = 100’ / 2π(R) is simplified to: R = 9000 / π = 2866.24’

Question

Hello, the below equation, and simplification of the equation, is offered in my study text.  What I would love to know, is what rule allows me to isolate the variable "R" on one side of the equation.  Maybe if someone recognized what type of equation this is, I could look it up and read about it, to get the understanding that I'd like.  It is an engineering study, which assumes I would already have the mathematical knowledge.
2° / 360 = 100’ / 2π(R)   is simplified to:  R = 9000 / π  =  2866.24’

jhonyy9 · Answer

so than i see it right what you wrote there this 2*pi*(R) this is formula for circumference of a circle where R mean the radius of this circle 

hope helped and i ve understood it right what you wrote above