Answer:
20
Step-by-step explanation:

multiply both sides by 35

divide both sides by 35

Answer:
160 cups of lemonade and 80 packages of cookies.
Step-by-step explanation:
l = lemonade
c = cookies
l+1.5c=280
2c=l
Substitute.
3.5c=280
Simplify.
c=80
Substitute into the second equation.
l=160.
Plug it back into the equations to check.
The answer to this question is the second choice
hope this helps:)