Removing which ordered pair will make the relation a function?

Solve the equation using the given values: x= -2.5; y= -7.51. 2xy + 2x²

How many lines can be drawn through points j and k? 0 1 2 3

2people are trying different phones to see which one has the better talk time. chatlong has an average of 18 hours with a standard deviation of 2 hours and talk-a-lot has an average of 20 hours with a standard deviation of 3. the two people who tested their phones both got 20 hours of use on their phones. for the z-scores i got 1 for the chatlong company and 0 for talk-a-lot. what is the percentile for each z-score?