triunghiul dreptunghic ABC are cateta AB=12 si AC=10. Aria acestui triunghi este egala cu cm patrati

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.

35=5×77=7×1when we simplify 7 by 7we will get 5 and 1, 5 divided by 1 is 5