Taylor is comparing the prices of two mattress cleaning companies. company a charges $30 per mattress and an additional $15 as service charges. company b charges $28 per mattress and an additional $21 as service charges. part a: write equations to represent company a’s and company b’s total mattress cleaning charges for a certain number of mattresses. define the variable used in the equations. part b: which company would charge less for cleaning 6 mattresses? justify your answer. part c: how much money is saved by using the services of company b instead of company a to clean 3 mattresses?