The equation that determines the number of used and new video games David can buy is 10x + 20y = 80. The combination (7, 2) does not represent a possible solution.
The equation in standard form that determines the number of used video games (x) and new video games (y) David can buy is: 10x + 20y = 80.
This equation represents the total cost of the video games, where the cost per used game is $10 and the cost per new game is $20.
To determine which of the following represents a possible combination of video games, we substitute the given values into the equation and check if the equation is true: (7, 2).
Plugging in the values, we have: 10(7) + 20(2) = 70 + 40 = 110 ≠ 80.
Therefore, the combination of (7, 2) does not represent a possible solution as it does not satisfy the equation.
The probable question may be:
David has $80 to spend on video games. Used video games cost $10 each, and new video games cost $20 each. Write the equation in standard form that determines the number x of used video games and the number y of new video games he can buy and determine which of the following represents a possible combination of video games. 10x+20y=80:(7,2)