Sam cut a pie into equal slices. there are only 3 slices left. the angle measure for the three slices is 72. how many slices did sam cut the pie into?

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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.