At a concession stan,one hot dog and one hamburger cost $2.75, one hot dog and seven hamburgers cost $11.75. find the cost of one hot dog and one hamburger i need with this question, i try so hard to get the answers and i can't

Variables:
cost of 1 hot dog = x
cost of 1 hamburger = y

Set up a system of equations and use substitution

x + y = 2.75
x + 7y = 11.75

x + y = 2.75 can be rewritten as y = -x + 2.75

x + 7 (-x + 2.75) = 11.25

-6x + 19.25 = 11.25

-6x = -8

x = .75

plug x back into other equation to find y

y = -.75 + 2.75

y = 2.00

1 hot dog = $0.75
1 hamburger = $2.00

Putting all the names in a hat and selecting six students because the rest would not have been random because you know who you picked just by looking but if u put names in a hat you don't know who you picked.