posted by mike on .
6 burgers and 3 hot dogs cost $27. 5 burgers and one hot dog cost $18.75. what is the price of a hot dog? what is the price of a hamburger?
first, represent unknowns using variables:
let x = price of hamburger
let y = price of hotdogs
set up equation:
(1) 6x + 3y = 27
(2) 5x + y = 18.75
there are several ways to solve this,, but id we use substitution method,,
choose an equation (in this case, equation (2)),, then express one of the variables in terms of the other,, thus if we express y in terms of x:
5x + y = 18.75
y = 18.75 - 5x
then we substitute this to equation (1):
6x + 3y = 27
6x + 3(18.75 - 5x) = 27
now simplify this and solve for x. after that substitute this x to either equations to get y.