Answer: 50 years old
Step-by-step explanation: Let's first use variables
to represent Devaughn's age and Sydney's age.
Although we don't know their exact ages, we know
the relationship between their ages.
In other words, if we call Sydney's age x,
Devaughn's age would then be x + 9.
Since the sum of their ages is 103,
we can create the equation x + (x + 3) = 103.
Simplifying on the left, we have 2x + 3 = 103.
-Subtract 3 from both sides
This gives us 2x = 100.
-Divide both sides by 2 to isolate x
This leaves us with x = 50.
Since we defined Sydney's age as x, we know Sydney is 50 years old.