You need to use PEMDAS (parentheses, exponents, multiplication, division, addition, subtraction)
3 - 3 x 6 + 2
FIRST, the multiplication:
= 3 - (3 x 6) + 2
= 3 - 18 + 2
NEXT, the addition:
= 3 - (18 + 2)
= 3 - 20
LAST, the subtraction:
= 3 - 20
= -17
SO, 3 - 3 x 6 + 2 = (-17)
