Answer:
5.5 years old.
Step-by-step explanation:
Let D represent present age of Robert's dog and C represent present age of Karen's cat.
We have been given that Robert's dog is 4 years older than Karen's cat. We can represent this information in an equation as:
[tex]D=C+4...(1)[/tex]
We are also told that in 3 years, the sum of the ages of Robert's dog and Karen's cat will be 13. After 3 years age of dog and cat would be [tex]D+3[/tex] and [tex]C+3[/tex] respectively.
We can represent this information in an equation as:
[tex]D+3+C+3=13...(2)[/tex]
From equation (1), we will get:
[tex]C=D-4[/tex]
Upon substituting this value in equation (2), we will get:
[tex]D+3+D-4+3=13[/tex]
Combine like terms:
[tex]2D+2=13[/tex]
[tex]2D+2-2=13-2[/tex]
[tex]2D=11[/tex]
[tex]\frac{2D}{2}=\frac{11}{2}[/tex]
[tex]D=5.5[/tex]
Therefore, Robert's dog is 5.5 years old right now.
