Last week Juan mowed lawns and walked his neighbor’s dog to earn money. For mowing lawns, he earned $6 less than twice as much as he did for walking dogs. Juan saves one-third of the money he earns and spends the rest. Let w be the amount Juan earned walking dogs. Then (2w 2 6) is the amount Juan earned mowing lawns. The total amount Juan earned is w 1 (2w 2 6), or 3w 2 6. Explain how you can find the amount of money Juan saved if he earned $12 walking dogs.