Mary and Jose each bought plants from the same store. Mary spent $89 on 7 cherry trees and 8 rose bushes. Jose spent $146 on 13 cherry trees and 11 rose bushes. What
was the cost of one cherry tree, x

The answer fam isPart A: Company A: y=30x+13 Company B: y=28x+15 
X: number of mattresses 
Y: total cost 
Part B: 

Company A: 30(4)+13= 133 Company B: 28(4)+15= 127 

Company B cost less than Company A does when you purchase 4 mattresses 
Part C: 
Company A: 30(7)+13= 223 
Company B: 28(7)+15= 211 
You save $12 by using the services of Company B instead of Company A to clean 7 mattresses