Two airplanes are each traveling at a constant speed. The table below shows the total number of miles the first airplane traveled as a function of time.
Hours
2 3 4
Total Distance (miles) 320 480 640
The equation y= ax represents the total number of miles, y, traveled by the second plane as a function of the numbers of hours, x,
If the second plane is traveling faster, then what must be true about a ?

Mrs. julien’s and mrs. castillejo’s classes are selling cookie dough for a school fundraiser. customers can buy packages of macadamia nut chip cookie dough and packages of triple chocolate cookie dough. mrs. julien’s class sold 25 packages of macadamia nut chip cookie dough and 30 packages of triple chocolate cookie dough for a total of $221.25. mrs. castillejo’s class sold 5 packages of macadamia nut chip cookie dough and 45 packages of triple chocolate cookie dough for a total of $191.25. (a) write the system of equations that model the problem. be sure to explain which equation represents which situation. (b) find the cost of each type of cookie. show your work. (c) explain which method you used to solve the system and why you chose that method.