When jane uses her calling card overseas, the cost of a phone call is .75 for the first three minutes and. 12 for each additional minute, thereafter. if jane plans to spend at most $3.60 to make a call, find the greatest possible length of talk time.

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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.