The equation a = a equals StartFraction 180 left-parenthesis n minus 2 right-parenthesis Over n EndFraction. represents the angle measures, a, in a regular n-sided polygon. When the equation is solved for n, n is equal to a fraction with a denominator of a – 180. What is the numerator of the fraction?

Question

Mercury · Answer

$$a=\frac{ 180(n-2) }{ n }$$

like the problem suggests, you'll need to solve for n, and your solution will be a fraction with denominator (a-180).

so, to start, multiply both sides by n 
distribute the 180(n-2)
combine like terms
factor out n again
divide by the coefficient of n to isolate n

let me know if you have any trouble with these steps or simply want to check your solution