Which of the following functions gives the length of the base edge, a(v), of a right square pyramid that is 8 inches tall as a function of its volume, v, in cubic inches?

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.