3. A group of students takes their math teacher out for
lunch. If five have hamburgers and four have hot
dogs, the bill will be $19.50. If four have hamburgers
and five have hot dogs, the bill will be $18.75. What
is the price of a hamburger?

what's that

add -60 to 120 which will result in : 2x+3y=180

then subtract 2x: 3y=-2x+180

lastly, divide by 2: y= -2/3x+60

hope this is the answer you're looking for: )

c) blue

lol  

why do you ask > .>

well, because the $0.25 is an added cost depending on how many minutes, the answer would be y = 30 + 0.25x.