As part of a school contest, sarah and luis are playing a math game. sarah must pick a number between 1 and 50 and give luis clues so he can write an equation to find her number. sarah says, "if i subtract 5 from my number, multiply that quantity by 4, and then add 7 to the result, i get 35." what equation can luis write based on sarah's clues and what is sarah; s clues and what is is sarah's number?