For several hours you watch a group playing dice on the street and you notice that the owner of the dice often wins. do you conclude that he is just very lucky? in two or more complete sentences, explain why or why not you conclude that the owner of the dice is lucky.

I conclude from the information given that he is just very lucky. I believe he is lucky, because it is very hard to perform tricks or deceive people with a dice. He may be cheating, but a dice can be very unpredictable, and he may just be skilled at the game. 

I have to assume that the instructions are to "simplify -5+7m-20=20-2m."

If that's the case:

Group like terms together:  7m + 2m = 20 +5 + 20
                                                9m      = 45
                                                  m   =  5 (answer)