Probability problem walkthrough.. how to solve with a tree diagram #conditionalprobability #math

This probability problem walkthrough shows how to solve the following question using a tree diagram:

"The probability that Jason will win his first tennis match is 80%. If he wins the first game, the probability of him winning the second game is 70%. If he loses the first game, the probability of him winning the second game is 90%. What is the probability that Jason will lose both games?"