Answer: 
Step-by-step explanation:

Answer:
3g+20
Step-by-step explanation:
Because Milena wants to have 3 cups per each guest and then she wants an additional 20 more.
Answer:(1,-1)
Step-by-step explanation:
Y= -2x+1
3x -2(-2x*1)=5
3x+(4x-2)=5
7x-2 =5
+2 = +2
7x=7
x= 1
Solution : (1,-1)