Remember your PEMDAS! Do your parenthesis first (4-2) and (6-2), then multiply (6-2) by 2, finish off your big parenthesis with addition and subtraction, and finally, multiply by three.
It should go something like this:
3[26 + (2) - (4)2]
3[26 + (2) - 8]
3[28 - 8]
3[20]
60