I believe that the owner of the dice is actually not lucky. There are people who practice throwing dice in a controlled way in order to get a specific side of the dice. If he practices his dice throwing a lot, then he would have a much higher chance of winning at a game of dice.
Step-by-step explanation:
Since you said he was lucky, I decided to make an answer saying that he wasn't lucky so you can choose between both of them. Your answer was good as well.
This is not an isosceles triangle because there are different angle measurements. The rule of an isosceles triangle is that it must always have two equal sides and angles.