Let sigma = (1, 2, 7, 6)(3, 2, 4, 1)(7, 8, 1, 2, 3) elementof s_8 (a) write sigma as a product of disjoint cycles, and as a product of transpositions (b) is sigma an even permutation or an odd permutation? (c) what is the order of sigma in s_8? (d) what is sigma^-1 in s_8?

check above link.

graphically?   well, you graph them both, the solutions is where they both intersect each other, since there are two solutions, meaning they will meet twice, or namely the linear will run into the quadratic curve twice, and where they meet, those x,y coordinates are the solutions to the system.