Ineed on my math homework.
a hairdresser is considering ordering a certain shampoo. company a charges $4 per 8-oz bottle plus a $10 handling fee per order. company b charges $3 per 8-oz bottle plus a $25 handling fee per order. how many bottles must the hair dresser buy to justify using company b? (answer in a complete sentence.)

i don't know what justify using company b means. can someone me?

Hi tissuebox, 

let x= the number of bottles the customers buys

first, lets consider how many bottles the customer must buy for the price to be the same no matter which company.

4x+10=3x+25
.
.
.
x=15, so at 15 bottles, the cost is the same for either company. At this point you look at x=16, one bottle higher, to compare costs, seeing that for company A this is $74 while for company B this is $73, so at 16 bottles company B is cheaper