How do you determine if a triangle is a right triangle given three points? problems and solutions?

Which of the following contains a variable?

Write an expression that represent sarah’s total pay last week.represent her hourly wage with w monday 5 tuesday 3 wednesday 0 noah hours wednesday 8 only with w wage did noah and sarah earn the same amount last week?

Emmanuel added 888 links per minute to his chain mail. allesia started 202020 minutes after emmanuel and added 131313 links per minute to her chain mail. how long had emmanuel worked when allesia caught up to him, and how many links had he added?