a few pre-calc questions?

Question

do not just give the answers please... give your reasoning. you do not have to do them all, just tell me the # before you answer

14.) Ace Prints will set up a printing job for $45, plus charge 2 cents per copy. Duce Prints charges 5 cents per copy but set up is only $30. What is the minimum number of copies that would make Ace cheaper than Duce? (and please do not just use guess and check)

26.) Factor: x^4 - 4
a. over integers.
b. over the real numbers
c. over the complex numbers

50.) In the first quarter of Homecoming game, School A outscored School B by 10 points. In the second quarter, B came back with twice as many points as A. In the third quarter, A scored 7 pts more than B had scored in the first quarter, and B scored 6 points less than A had scored in the first quarter. In the fourth quarter, A scored 1 point less than they had in the second quarter, and B scored 3 points more than A. If A led B by a score of 20-17 at halftime, who won and what was the score

Answer 1

14.) 4500 + 2x = 3000 + 5x (x = number of copies)
1500 = 3x
x = 500 copies (precisely at 500 copies the price is the same for both, below 500 copies Duce is cheaper)
hereby follows: 501+ copies of Ace are cheaper than 501+ copies of Duce

26.a,b,c) x^4 - 4 = (x^2 + 2) * (x^2 - 2)

50.) damn, that's too much for a drunken guy - LOL