Question

For every problem answered correctly on an exam, 3 points are awarded. For every incorrect answer 4 points are deducted. In a 10-question test a student scored 16 points. How many correct and incorrect answers did he have on the exam?

Answer 1

r+w=10
3r-4w=16

Answer 2

ok did that got to x =30+12y

Answer 3

let x = correct answers, and y = incorrect ansewrs
we can make these equation from the question:
x+y=10 which is the number of questions given and,
3x-4y=16 which is the amount of score you get and then solve them.
you can use calculator to solve them out :D

Answer 4

1. Multiply equation 1 by 4.
2. Add the result of step 1 to equation 2
3. Divide both sides of the answer to step 2 by 7

Answer 5

youll get x=10-y, then sub into second equation:
3(10-y) - 4y = 16,
30 - 3y -4y = 16
7y = 14, y = 2
then sub the value back in eq 1,
x + 2 = 10
x=8

Answer 6

Thank you! You have no idea how long I was stuck on that! Bless you both! :)

Answer 7

no problem :D