A cleaning company charges x dollars per hour to clean floors and y dollars per hour to clean the rest of a house.-When the company spends 2 hours to clean floors and 3 hours to clean the rest of a house, the total charge is $84.-When the company spends 1 hour to clean floors and 4 hours to clean the rest of a house, the total charge is $87.Which ordered pair represents the hourly charges to clean floors and to clean the rest of the house?A. (12, 20)B. (15, 18)C. (18, 15)D. (20, 12)Note: Please show work. My teacher checks it.
Accepted Solution
A:
The answer is B. (15,18)
Solution:
First, let's set the variables first.
X = dollars per hour to clean the floor Y = dollars per hour to clean the rest of the house
For the first statement, "2 hours to clean floors and 3 hours to clean the rest of a house, the total charge is $84" We can put it into an equation. 2X + 3Y = 84 ⇒ equation 1
For the first statement, "1 hour to clean floors and 4 hours to clean the rest of a house, the total charge is $87' X + 4Y = 87 ⇒ equation 2
Multiply first equation 2 by 2 to make the coefficient of both equations 1 and 2 the same.