Scores and subtracting from total score

[hc_wolf]

Question I have a Int ScoreBlue;

As smething is destroyed the score increase. ScoreBlue = ScoreBlue + 10;

Is there a way to subtact from the Total in the int ScoreBlue; ?

Which of these would be best or something else?

ScoreBlue = ScoreBlue - 10;

or

ScoreBlue -= 10;

or

ScoreBlue =( 10-ScoreBlue )

something else?