The distance around a closed shape can be expressed as 3 times the length of side s or 3s draw an example of this geometric shape (what shape do I draw)

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.