Choose the equations that are not linear equations. - x - y = 2, x^2 + y = 4, x/2 - y^3 = 1, x = 5

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?

Which graph has a rate of change of zero

Express -5 2/5 as an improper fraction.