Answer:

Explanation:
The exercise is: " Evaluate
when
and

Given the following expression:

You can follow these steps in order to evaluate it:
1. Substitute
and
into the expression provided in the exercise:

2. Solve the multiplications. Remember that:

Then:

3. Reduce the fraction. Notice that the numerator 6 and the denomiantor 4 can be both divided by 2. Then:

4. Solve the addition:

Since the number 21 has a denominator 1, the Least Common Denominator is:

Then, the sum is:
