An easy way to do this is to do trial and error.
All possible places to put the bracket:
a) (25 - 8) - 2 = 19 But since BEDMAS goes from left to right with Addition and Subtraction, the equation is unaffected.
b) 25 - (8 - 2) = 19
25 - 6 = 19
Therefore b) is correct.
