Write inequalites to describe the region. the region consisting of all pints between(but not on ) the spheres of radius r and r centered at the origin, where r

Convert 2000 swiss francs to dutch guilders

y=2x−1 5x−4y=1 is (1,1)(1,1) a solution of the system?

One cell phone plan charges $20 per month plus $0.15 per minute used. a second cell phone plan charges $35 per month plus $0.10 per minute used. write and solve an equation to find the number of minutes you must talk to have the same cost for both calling plans.