The graph shows thar video sales at Bart's are nost often. a- more than 400
b- less than 300
c- less than 100
d- more than 300​

The answer is b

Less than 300

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.