Evaluate -a/b: Solving with Values (8,-4) and (-8,4)

$-\frac{a}{b}$

Substitute the following into the expression above and solve.

1. $b=-4,a=8$

2. $b=4,a=-8$

Let's start with the first option.

Let's substitute the data into the expression:

$-\frac{8}{-4}=$

First, we can see that in the fraction we are dividing a positive number by a negative number, therefore the result will be negative:

$-\times-\frac{8}{4}=$

Now we can see that we have a multiplication between two negative numbers and therefore the result must be positive:

$+\frac{8}{4}=2$

Let's continue with the second option.

Let's substitute the data into the expression:

$-\frac{-8}{4}=$

First, we can see that in the fraction we are dividing a positive number by a negative number, therefore the result will be negative:

$-\times-\frac{8}{4}=$

Now we can see that we have a multiplication between two negative numbers and therefore the result must be positive:

$+\frac{8}{4}=2$

Therefore the final answer is:

$1,2=+2$