I just need the answers to these and I'll be done with my homework.Please help

Answer:
[tex]3) x = 12, \ y = \frac{x}{3} = \frac{12}{3} = 4[/tex]
[tex]4) x = 2 , \ y = 5x + 9 = ( 5 \times 2 ) + 9 = 10 + 9 = 19[/tex]
[tex]5. a ) Profit = Cost \ Price - Selling\ Price[/tex]
Profit = P, Cost C,
[tex]P = 0.50C - 75[/tex]
[tex]b) Break \ even\ means \ zero \ profit[/tex]
[tex]P = 0.50C - 75 \\\\0 = 0.50C - 75\\\\0.50C = 75\\\\C = \frac{75}{0.50} = 150[/tex]
Number of cups to break even is 150 cups.