SOLUTION: solve 6 absolute 3x+3=15

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Question 4368: solve 6 absolute 3x+3=15
Found 2 solutions by IREZ, rapaljer:
Answer by IREZ(1) About Me  (Show Source):
You can put this solution on YOUR website!
3x+3=15
Add 3 to both sides cancelling out the 3 on the left leaving you with
3x=18
then you can divide by 3 on both sides cancelling out the other 3 on the left and leaving you with x=6


This is WRONG!
subtract 3 from both sides:
3x = 12
then x = 12/3
--> x= 4

Jon.

Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
IF the problem correctly stated is 6+%2A+abs%283x%2B3%29+=+15, then TWO solutions must be considered.

Begin by dividing both sides of the equation by 6, giving
%286+%2A+abs%283x%2B3%29%29%2F6+=+15%2F6 or
%286+%2A+abs%283x%2B3%29%29%2F6+=+5%2F2,

The first solution is 3x%2B3+=+5%2F2, The second solution is 3x+%2B+3+=+-5%2F2

For all those fraction haters out there, let's multiply both sides of BOTH equations by 2, and get rid of the fractions. Now it looks like this:
2%283x%2B3%29+=+5 and 2%283x%2B3%29+=+-5
+6x+%2B+6+=+5 and 6x%2B6+=+-5

Subtract 6 from each side:
6x+=+-1 and 6x+=+-11
x+=+-1%2F6 and x+=+-11%2F6

Check in the original equation:
6+%2A+abs%283x%2B3%29+=+15

For x=-1%2F6,
6+%2A+abs%283%2A%28-1%2F6%29%2B3%29+=+15
6+%2A+abs+%28-1%2F2+%2B+3%29+=+15
6+%2A+5%2F2+=+15

For x=-11%2F6
6+%2A+abs%283%2A%28-11%2F6%29+%2B+3%29+=+15
6+%2A+abs%28-11%2F2+%2B+3%29+=+15
6+%2A+abs%28+%28-5%2F2%29%29+=+15

R^2 at SCC