Question
A math contest consists of ten problems.Three points are given for each correct answer. One point is deducted for each incorrect answer. Andy answers all the problems and scores 18 points. How many correct answers does he have?
Answers
rbowh
x = number of answers
y = number of incorrect answers
3 x - y = 18
x + y = 10
add the two equations and solve for x
check your answer
y = number of incorrect answers
3 x - y = 18
x + y = 10
add the two equations and solve for x
check your answer
matt
How do you that rbowh? I am really bad at this.(step by step please)
Ms. Sue
What part of the explanation don't you understand?
matt
How to solve for x.(i am terrible at this)
rbowh
what did you get when you added the two equations?
matt
That is what I don't get.Please can you show me how to do it.
rbowh
by the way, x represents number of correct answers - I left that out initially
matt
Step by step is what I meant.
rbowh
(3x - y) + (x + y) = 18 + 10
4 x = 28
x = ?
4 x = 28
x = ?
matt
Thank you very kind sir/ma'am you were a big help.
rbowh
You're welcome Matt.
ANIKA
3*0=0
3*1=3
3*2=6
3*3=9
3*4=12
3*5=15
3*6=18
3*1=3
3*2=6
3*3=9
3*4=12
3*5=15
3*6=18
sergio
3x+y=18
x+y=10
x=4
x+y=10
x=4