Okay let’s put PEMDAS into mind.
PEMDAS: parenthesis, exponents, multiplication, division, addition, subtraction (left to right)
18-9•(-4) /3 +10•2
Multiplication & Division comes first (left to right) so...
-9•(-4) = 36
bring down the divided by 3...
36/3 = 12
Bring the whole equation down...
18+12+10•2
Once again, there is another to multiply so...
10•2 = 20
18+12+20
All is the same so add them up to get...
50
^ That’s the answer.