Shayne wants to earn money to attend a basketball camp. For her 8th-grade graduation,
her grandmother gave her part of the money she needs. Every month since then, Shayne
has been saving the same amount from her babysitting jobs. After 3 months she had
$155, and after 7 months she had $295. Which equation describes the relationship
between x, the number of months Shayne has been saving, and y, the amount she has
saved?