Explanation:
Something to keep in mind is that anything greater than 0 is positive and anything less than 0 is negative
a is to the right of 0 and 1 making it a positive number
b is to the left of 0 making is a negative number
A. a is greater than 1 and b is a negative number
negative number * positive number = negative number
We already know that a is greater than 1 so ab has to be much less than -1 making ab+1 a negative expression
B. Looking at the number line, you can tell that the distance between 1 and a is a bit less than the distance between 0 and 1
This means that a= 1.x not 2
Because of this, a-2 is negative
C. -b
b is a negative number which means that -b would be positive
D. a+b
Looking at the number line, you can tell that the distance between 0 and a is less than the distance between 0 and b
Therefore, a+b is negative
E. a-b
Since b is already negative, the expression would simplify to two positive numbers being added
This means that a-b can't be negative
F. a-1
The number line shows us that a is greater than 1, therefore, a minus 1 would be positive
I hope this helps in some way or another