An electric company charges a $40 monthly fee plus a usage fee of $0.02 per kilo-watt-hour. A 7% tax is added to each bill. Write an equation that models the total monthly payment, y, for x kilowatt-hours used.

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?

Bring the fraction a/a-4 to a denominator of 16-a^2

If the value of cos330°is√3/2 then find cos 165°.