Answer:
a single burger costs $2, and a single soda costs $1.
Step-by-step explanation:
Lets set up a system of equations, with b for the burgers and s for the sodas
3b + 3s = 12
5b + 3s = 18
rewriting to switch the order of the equations
5b + 3s = 18
3b + 3s = 12
Then, we need to eliminate one variable to make it easier for us to find both, let's eliminate s by multiplying the entire bottom equation by -1
5b + 3s = 18
-3b - 3s = -12
adding the two together, we get
2b = 6
divide by 2 on both sides and we get
b = 3
THen, we take that value and plug it in to either of our first two equations (I'm using the first equation), and we get
3* 3 + 3s = 12
multiply
9 + 3s = 12
subtract 9 from both sides
3 s = 3
divide both sides by 3
s = 1
this means that a single burger costs $2, and a single soda costs $1.
