Well, the answer is 12. This is because you need to add the inverse operation. So for (6x-6) You add 6 or the second number( the one that doesn't have the x in front of it)because it is the opposite/inverse operation.You basically just add 6 and because the opposite of subtraction is addition. You then cross is out because it will equal zero. Then with the 6x, you add 6 as well because what you do to one side, you must do the same to the other. so 6+6=12. SO x=12.
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It would be one fourth cause he tells you the fraction of how many guppies are red
