You don’t need parentheses if the order of operations follows PEMDAS or BODMAS priority rules.
In this case we would get: 32-10+2=24 because the multiplication and division operations are done first.
But you can make this more explicit by using parentheses:
(8*4)-(2*5)+(4/2). When you do this it leaves no doubt about what is intended.
The result is so different if we do this, for example: