This is a problem that I have to solve with matrixes, Please show me all of the work. I will award brainliest.

At a particular swim meet, 10 points were awarded for each first-place finish, 8 points for second, and 7 points for third.

Washington High School had 10 first place finishes, 6 second place finishes and 2 third place finishes.
Johnson High School had 8 first place finishes, 9 second place finishes and 1 third place finish.
Roosevelt High School had 4 first place finishes, 5 second place finishes and 4 third place finishes.
Lewis High School had 3 first place finishes, 3 second place finishes and 6 third place finishes.
Find the total number of points for each school. Which school won the meet? Which school came in second and what was the difference?