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davie08
Aug5-11, 01:24 PM
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.
Mark44
Aug5-11, 01:26 PM
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.
The equation is linear, so there can be only one solution (x = 1/2). Are you sure you have written the equation correctly?
davie08
Aug5-11, 01:28 PM
I meant to say 1/2 or -1 but I feel like they screwed up its a sample placement test with my university.
Mark44
Aug5-11, 01:29 PM
The only solution to the equation you gave is x = 1/2.
davie08
Aug5-11, 01:31 PM
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.
eumyang
Aug5-11, 05:21 PM
1. The problem statement, all variables and given/known data
if (4x+1) + 6 = 9, then x=?

...

the answer is -1 and 1/2, but how could -1 work wouldn't that make the answer 3 instead of 9.
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.
Mark44
Aug5-11, 06:14 PM
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.

I'll bet that's it. My thought was that there might be an exponent missing, but that didn't work out.
HallsofIvy
Aug6-11, 05:25 AM
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.
The other possibility is that some fool, who typed up the exam, replaced "|" with "(" and ")"!
shiva999
Aug6-11, 05:29 AM
answer is only 1/2,and i dont know how you got -1.
HallsofIvy
Aug6-11, 06:57 AM
answer is only 1/2,and i dont know how you got -1.
Did you not read the other replies? The problem is, almost certainly, to solve
|4x+ 1|+ 6= 9, not (4x+ 1)+ 6= 9.
Ray Vickson
Aug6-11, 02:25 PM
Did you not read the other replies? The problem is, almost certainly, to solve
|4x+ 1|+ 6= 9, not (4x+ 1)+ 6= 9.

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

RGV