# Basic solving for variable question.

1. Aug 5, 2011

### davie08

1. The problem statement, all variables and given/known data
if (4x+1) + 6 = 9, then x=?

2. Relevant equations

3. The attempt at a solution

the answer is -1 and 1/2, but how could -1 work wouldn't that make the answer 3 instead of 9.

2. Aug 5, 2011

### Staff: Mentor

The equation is linear, so there can be only one solution (x = 1/2). Are you sure you have written the equation correctly?

3. Aug 5, 2011

### davie08

I meant to say 1/2 or -1 but I feel like they screwed up its a sample placement test with my university.

4. Aug 5, 2011

### Staff: Mentor

The only solution to the equation you gave is x = 1/2.

5. Aug 5, 2011

### davie08

okay thanks I've never had a question answered so fast in a forum before, I was trying out this forum compared to another one but this forum wins hands down lol.

6. Aug 5, 2011

### eumyang

I still think there's a possibility that you didn't copy the question right. If there were absolute value symbols instead of parentheses:
|4x+1| + 6 = 9
... then there would indeed be two solutions, -1 and 1/2.

7. Aug 5, 2011

### Staff: Mentor

I'll bet that's it. My thought was that there might be an exponent missing, but that didn't work out.

8. Aug 6, 2011

### HallsofIvy

Staff Emeritus
The other possibility is that some fool, who typed up the exam, replaced "|" with "(" and ")"!

9. Aug 6, 2011

### shiva999

answer is only 1/2,and i dont know how you got -1.

10. Aug 6, 2011

### HallsofIvy

Staff Emeritus
Did you not read the other replies? The problem is, almost certainly, to solve
|4x+ 1|+ 6= 9, not (4x+ 1)+ 6= 9.

11. Aug 6, 2011

### Ray Vickson

Either that, or the questioner wrote "and" instead of "or" in a multiple-choice setting (or the OP copied the question incorrectly).

RGV