I need help fast I forgot how to do this

Can you me find the missing length. i attached an image.

Sanjay solved the equation below. which property did he use to determine that 7x+42=42 is equivalent to 7(x+6)=42 7x+42=42 7x=0 x=0

6. tim is trying to study but hours go by and he doesn't get anything done. what time management advice would tim? work in smaller chunks of time an hour or less whenever you have a few minutes to spare. create flashcards. talk to your instructor right away and make a plan together for how you can get back on track, take scheduled breaks only or allow yourself only 5-10 minute breaks find somewhere quiet like a library or school to study tum off your phone and/or tell others you are busy