How many solutions does the following equation have |6×+12|=-18

This equation has no solution.

Reason: 
The absolute valued function, which is represented by straight bars, returns only positive values.
For example | - 5 | = 5
A negative result cannot be obtained from an absolute valued function. Since the given equation makes the absolute valued function equal to a negative value, which is not possible, so the equation has no solution or root. 

The first one, i believe, would be correct. all the others have one thing in common, and that's that they have repeating numbers. in the second one, x and y have repeating 6's and 3's, and in the third, x and y have repeating 6's as well. in the last one, there are repeating 3's. the first one has no repeating numbers.