-9
=
-9
............ addition and subtraction = subtraction.
-9*- 10
=9* 10=90 ...
-5-[-4]=
-(5-4)=- 1 ... The subtraction of two negative numbers is equal to the subtraction of positive numbers.
-7-[-8]=
-(7-8)= 1 ... Subtracting two negative numbers equals subtracting a positive number and then taking a negative number.
-9/-3
=
9/3
=3
.................................................................................................................................................................................
The result of multiplication and division with the same sign is positive
The result of multiplication and division of different symbols is negative.
......