SOLUTION: The score on a trivia game is obtained by subtracting the number of incorrect answer from twice the number of correct answer. If a player answered 50 total question and obtained a

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Question 1103333: The score on a trivia game is obtained by subtracting the number of incorrect answer from twice the number of correct answer. If a player answered 50 total question and obtained a score of 40 , how many questions did the player answer correctly?
Found 2 solutions by algebrahouse.com, greenestamps:
Answer by algebrahouse.com(1659) About Me  (Show Source):
You can put this solution on YOUR website!
x = number of incorrect answers
y = number of correct answers

x + y = 50 {there were 50 total questions}
2y - x = 40 {subtract incorrect answers from twice correct answers to obtain score}

x + y = 50 {first equation}
-x + 2y = 40 {re-arranged second equation}
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3y = 90 {added the two equations}
y = 30 {divided each side by 3}

the player answered 30 questions correctly

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Answer by greenestamps(13203) About Me  (Show Source):
You can put this solution on YOUR website!


His score of 40 was +2 points for each of the x questions he answered correctly plus -1 point for each of the (50-x) questions he answered incorrectly:

2x-%2850-x%29=+40
2x-50%2Bx+=+40
3x+=+90
x+=+30

He answered 30 questions correctly.

CHECK: 30*2 - 20*1 = 60-20 = 40