Final answer:
By creating equations based on the given information and solving for Lisa's score first, we determined that Jane scored 8 points in the computer game.
Step-by-step explanation:
To find out how many points Jane scored in the computer game, let's use algebra. First, let's define Jane's score as J and Lisa's score as L. According to the problem, Jane's score is 12 points less than twice Lisa's score, which gives us the equation J = 2L - 12. We're also told that the total score is 18 points, so J + L = 18.
To solve for Jane's score, we can substitute the first equation into the second: (2L - 12) + L = 18. This simplifies to 3L - 12 = 18. Adding 12 to both sides gives us 3L = 30. Dividing both sides by 3, we find out that Lisa's score L is 10. Applying this to Jane's score equation: J = 2(10) - 12, we get J = 20 - 12, which equals 8. Therefore, Jane scored 8 points in the game.