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:
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 
and 
respectively.
We can represent this information in an equation as:
From equation (1), we will get:
Upon substituting this value in equation (2), we will get:
Combine like terms:
Therefore, Robert's dog is 5.5 years old right now.
2. unit price = $ ÷ oz
<span>a) 64 fl oz for $2 = 2/64 ≈ $0.031 per ounce </span>
<span>b) 256 fl oz for $7.5 = 7.5/256 = $0.029 per ounce </span>
<span>c) buy wholesale because 0.029 < 0.031 </span>
<span>3. unit rate means 1 for the miles </span>
<span>3/10 in ÷ 7/8 mi </span>
<span>= 12/35 inches per mile ...</span>
Tomas used incorrectly the rule of signs, the expression should be simplified as follows:
-2.6 + (-5.4)
-2.6 -5.4 = 8
<h3>
</h3><h3>
What mistake did Tomas likely make?</h3>
Here Tomas wants to perform an addition between two numbers:
-2.6 + (-5.4)
And the outcome that Tomas gets is:
-2.6 + (-5.4) = 2.8
Here his mistake seems to bee that he thought the second number was a positive number, and he solved the operation:
-2.6 + 5.4
So, he used wrong the rule of signs.
Remember that the rule of signs says that:
(-)*(+) = (+)*(-) = (-)
Using that, we can rewrite the original expression:
-2.6 + (-5.4)
to:
-2.6 - 5.4
Solving that, we get:
-2.6 - 5.4 = -8
Which is the outcome that Tomas would have gotten if he had used correctly the rule of signs.
If you want to learn more about the rule of signs:
brainly.com/question/13333620
#SPJ1
