How do you solve: f(x) = x^2 - 6x + 8

I need to understand how to solve this so please show work, thank you!

Use the elimination method to solve the systems of equations.choose the correct ordered pair. 7x+4y=39

Students are given 3 minutes to complete each multiple-choice question on a test and 8 minutes for each free-responsequestion. there are 15 questions on the test and the students have been given 55 minutes to complete itwhich value could replace x in the table? 5507-m23-m8(15-m)8(15)-m

Jon’s weight loss for each week of the month is 5 lbs., 2.5 lbs., and 2.5 lbs. he gained 3.5 lbs. the last week. if jon originally weighed 198 lbs., how much does he weigh now?