Answer:
The answer would be he sold 11 packs of baseball cards at $0.75 each.
Step-by-step explanation:
11 packs of cards at 75 cents each.
Answering from phone so this will be a bit messy.
a
b=a+1
c=b+1=a+2
2a=b+20
Therefore:
2a=a+1+20
a=21,b=22,c=23
Answer:
A variable.
Step-by-step explanation:
In 3x, 3 is constant and x is a variable but together, 3x is a variable.