How this 0=t2−t−2 become this 0=(t−2)(t+1)

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?

Find the commission on a $590.00 sale if the commission is 15%.

Tom is buying topsoil for the flower bed shown below. one bag of topsoil covers 15 square meters. how many bags of topsoil does tom need to cover his flower bed?