We can see that the line is horizontal so its slope is 0.
Expression consists of numbers, variables, and mathematical operations. The expression f(w)=5(w+4) is equal to f(9)=5(9)+20.
<h3>What is an Expression?</h3>
In mathematics, an expression is defined as a set of numbers, variables, and mathematical operations formed according to rules dependent on the context.
The expression is given to you is,

Now, if we solve the expression it can be written as,

substituting the value of w, we will get,

Hence, the expression f(w)=5(w+4) is equal to f(9)=5(9)+20.
Learn more about Expression:
brainly.com/question/13947055
Answer: The length is 3 or 9 hope this helps.
Step-by-step explanation:
yards, there are 3 feet per yard