NEED HELP FASt will give brain and high rating pleassee and thank you :)

Matt and brian were solving a system of equations. they both noticed that the two lines had the same slope. brian said that because each line in the system had the same slope, the two lines had to be parallel, which meant the solution to the system was "no solution" matt disagreed, and said they should also look at the y-intercepts before determining how many solutions there were. who is correct?

How do i solve using pythagorean theorem?

We just started the introduction into circles and i have no idea how to do this.