Answer:
4p+2d=20.5
6p+4d=34.50
popcorn cost: 3.25
drink cost: 3.75
Step-by-step explanation:
1) Assigning a variable
p=popcorn
d=drinks
2) Writing the system of equations
4p+2d=20.5
6p+4d=34.50
3) Simplifying one equation
2d=20.5-4p
d=10.25-2p
4) Substitution
6p+4d=34.5
6p+4(10.25-2p)=34.5
6p+41-8p=34.5
-2p+41=34.5
-2p=-6.5
p=3.25
5) Finding d
d=10.25-2(3.25)
d=10.25-6.5
d=3.75