Here is the full question
Two rival dry cleaners both advertise their prices. Store A's prices are modelled by the expression (15x -2), where x is the number of items brought in. Store B's prices are modelled by the expression 3(5x+7) , where x is the number of items brought in. When do the two stores charge the same rate?
Answer:
The two stores cannot charge at the same rate.
Step-by-step explanation:
From the information given above:
Two rival dry cleaners both advertise their prices.
Store A's prices are modelled by the expression (15x -2)
Store B's prices are modelled by the expression 3(5x+7)
The objective is to determine the period at which the two stores charges at the same rate;
To do that, we need to equate the expression in store A and B
i.e.
15x - 2 = 3(5x + 7)
Open brackets
15x - 2 = 15x + 21
Deduce both sides by - 15x
- 2 = 21
Therefore; since the value of x cannot be estimated, then the two stores cannot charge at the same rate.
