Answer
The contestant answered 13 questions correctly, and 7 were incorrectly answered.
Work Step by Step
Let x = the number of correct answers
y = the number of incorrect answers
A contestant on a quiz show gets 150 points for every correct answer and loses 250 points for each incorrect answer. The contestant completed 20 questions. Hence, we get the system of equations:
$x+y=20$
$150x-250y=200$
The first equation will be: $y=20-x$
Write the second equation. Substitute 10x + 50 for y.
$150x-250(20-x)=200$
$150x-5000+250x=200$
$400x=5200$
$x=13$
Solve for $y$: $13+y=20$
$y=7$
The contestant answered 13 questions correctly, and 7 were incorrectly answered.
