AB and CD intersect at Q and R is in the interior of angle AQC. If the measure of angle DQA = 2x-y, the measure of angle AQR = x and the measure of angle RQC = y, find the values of x and y so that AB is perpendicular to CD.

Asales representative from a local radio station is trying to convince the owner of a small fitness club to advertise on her station. the representative says that if the owner begins advertising on the station today, the club's total number of members will grow exponentially each month. she uses the given expression to model the number of club members, in hundreds, after advertising for t months.