Whats a good way to remember then lesson you just went over ?

A good way is to make flashcards and review the information you just learned. You can also test yourself this way, whoch could help. Use online websites such as quizlet to help you. Review after an hour you learned, then a day, then a week, then a month and so on to remember.

hope this helps!

Step-by-step explanation:

answer: y=0 if that is what u r looking for

m∠a is 90°

m∠b is 40°