Solve proportions
13/25 = p/100

you divide the cost ($15) by the quantity (6) to get your questions answer. the yo-yo costs $2.50. hope this : )!

step-by-step explanation:

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.