Linda is saving money to buy a bike. She has $63 and is going to save an additional $9 each week. The bike costs . In how many weeks will she have enough money to buy the bike?

Solve the system of equations. y= 2x y= x^2 - 15

An automated water dispenser fills packets with one liter of water on average, with a standard deviation of 5 milliliter. the manual says that after a year of operation the dispenser should be tested to see if it needs recalibration. a year later a number of filled packets are set aside and measured separately. it is found that the average packet now contains about 0.995 liters. does the dispenser need calibration? explain your answer.

Sam claims that cos x =sin y if x and y are congruent angels. is sam correct ?