If the variance of the data values in a population is 169, what is the standard deviation of data values?

Solve the system by the elimination method. 2x + y - 4 = 0 2x - y - 4 = 0 when you eliminate y, what is the resulting equation? a.x = 0 b.4x = -8 c.4x = 8

What is sin 7x/4 ? i need on this urgent trig

You are a clerk at convenience store. a customer owes 11.69 for a bag of potatoes chips. she gives you a five dollar bill. how much change should the customer receive?