Manuel had some marbles. he gave lily half of his marbles plus one. he gave matt half of his remaining marbles plus two more. he had five marbles left in the end, how many did he gave left in the beginning?

The question is:  What did he have in the beginning ?  All the information
we have happened after that.  So if we want to work through the information
towards the answer, maybe it makes sense to solve it starting from the end,
working backwards toward the beginning.

Manuel had  5  marbles left at the end of the story. 

Those  5  remained after he gave Matt  2 . 
Before he gave Matt  2, he had  7 .

Those  7  remained after he gave Matt half of his marbles.
Before he gave Matt half of his marbles, he had  14 .

Those  14  remained after he gave Lily  1  marble.
Before he gave Lily  1  marble, he had  15 .

Those  15  remained after he gave Lily half of his marbles.
Before he gave Lily half of his marbles, he had  30 .

No a triangle cannot be formed because when you add the two smallest number together (which would be 11) the have to be bigger than the number it is "against" ( which would be 12)