Use the row operations tool to solve the following system of equations, obtaining the solutions in fraction form.
3x + 2y + 8z = -5
7x + 2y + 6z = 6
9x + 2y + 3z = 2
give the values for x, y, and z with the fractions reduced to lowest terms (for example 1/2 rather than 3/6).
x =
y =
z =

Find the cosine function that is represented in the graph.

Amovie streaming service charges it’s customers $15 a month. martina has $98 saved up. will she have any money left over if she pays for the maximum amount of months she can afford? explain.

Arandom sample of 15 observations is used to estimate the population mean. the sample mean and the standard deviation are calculated as 172 and 63, respectively. assume that the population is normally distributed. a. with 99 confidence, what is the margin of error for the estimation of the population mean? b. construct the 99% confidence interval for the population mean. c. construct the 95% confidence interval for the population mean. d. construct the 83% confidence interval for the population mean. hint: you need to use excel function =t.inv.2t to find the value of t for the interval calculation.