The mathematics department of a college has 12 male professors, 7female professors, 13 male teaching assistants, and 12 female teaching assistants. if a person is selected at random from the group, find the probability that the selected person is a professor or a male.

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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.