Techwiz electronics makes a profit of $35 for each mp3 player sold and $18 for each dvd player sold. last week, techwiz sold a combined total of 121 mp3 and dvd players. let x be the number of mp3 players techwiz sold last week. write an expression for the combined total profit (in dollars) techwiz made from mp3 and dvd players last week. total profit in dollars =