Elimination Method

If we multiply the equation 3 by (-1) we obtain this:

If we add them we obtain 0, therefore there are infinite solutions. So, let's write it in terms of Z
1. Using the 3rd equation we can obtain X(Y,Z)

2. We can replace this value of X in the 1st and 2nd equations

3. If we simplify:

4. We can obtain Y from this two equations:

5. Now, we need to obtain X(Z). We can replace Y in X(Y,Z)

6. If we simplify, we obtain:

7. In conclusion, we obtain that
(X,Y,Z) =
There are a lot of rational number between 7.7 and 7.9, but the problem asked to find only one ratio number, so I will choose one which is 7.8. 7.8 is a rational number because ration number means that it can change into a fraction or improper fraction.
Now, let's change 7.8 into the fraction
First of all, change this into mixed number:
7.8
=7 8/10
=7 4/5
Then, change this into improper fraction.
Step 1:
Numerators:
7×5+4=39
Step 2:
Denominator
5, so your final answer will be 39/5. Hope it help!
Answer:
40+11q
Step-by-step explanation:
5x+qy when x=8, y=11
5(8)+q(11)=40+11q