Uhh, these give me a headache, I think number 2 is array..
Answer:
2(d - 3) is the equation. You cannot solve for d. You can only simplify it
600,000,000+40,000,000+400,000+9,000+200+10
Solution:
Let x = the number of $70 seats sold
Let y = the number of $20 seats sold
x+y ≤ 20,000
70x+20y > 500,000
