Olivia is taking a test that has 30 questions.She earns 9 points for every correct answer and loses 5 points for every wrong answer (questions left blank also count as wrong answers) . If Olivia’s score is 18 , how many questions did she answer correctly on the test .

Answer 1

number correct --- x
number wrong ---- 30-x

9x - 5(30-x) = 18

solve for x

Answer 2

So if x is 12 that means she got 12 correct and 18 wrong and that’s why the score is an 18 ?