Step-by-step explanation:
You just have to plug the numbers they give you into the equation. For the first one, you have 0 + 5y = 10; 5y = 10; y = 2. For the second one, x + 5(0) = 10; x + 0 = 10; x = 10. And lastly, for the third one, x + 5(6) = 10; x + 30 = 10; x = -20.
For all of the questions or only one-?
If 2 gallons of oil are used a day, than he will need 60 gallons of oil, because 30x2=60. For 60 gallons of oil, you would have to have 12 drums because 60÷5=12. Because there is already 8 drums of oil, there would already be 40 gallons because 8x5=40. If the owner already had 40 gallons of oil, they would only have to get 20 more gallons because 60-40=20. That would be 4 drums because 20÷5=4. The owner would have to order 4 more drums of oil.