Answer :
- Substitute $x = 6$ into the function $f(x) = 7x - 4$.
- Calculate $7 Imes 6 = 42$.
- Subtract 4 from 42: $42 - 4 = 38$.
- The final answer is $\boxed{38}$.
### Explanation
1. Understanding the problem
We are given the function $f(x) = 7x - 4$ and we want to find the value of $f(6)$. This means we need to substitute $x = 6$ into the expression for $f(x)$.
2. Substituting x = 6
To find $f(6)$, we replace $x$ with $6$ in the expression $7x - 4$. So we have:
$$f(6) = 7(6) - 4$$
3. Performing the multiplication
Now we perform the multiplication:
$$f(6) = 42 - 4$$
4. Subtracting to find the final value
Finally, we subtract to find the value of $f(6)$:
$$f(6) = 38$$
5. Final Answer
Therefore, $f(6) = 38$.
### Examples
In real life, this type of function can model various scenarios. For example, imagine a taxi service charges a fixed rate per mile, with an additional flat fee. If the rate is $7 per mile and the flat fee is $4 less than the total, the function $f(x) = 7x - 4$ can represent the total cost for a ride of $x$ miles. Evaluating $f(6)$ would then tell you the cost of a 6-mile ride. Understanding function evaluation is crucial for making predictions and decisions based on mathematical models.
- Calculate $7 Imes 6 = 42$.
- Subtract 4 from 42: $42 - 4 = 38$.
- The final answer is $\boxed{38}$.
### Explanation
1. Understanding the problem
We are given the function $f(x) = 7x - 4$ and we want to find the value of $f(6)$. This means we need to substitute $x = 6$ into the expression for $f(x)$.
2. Substituting x = 6
To find $f(6)$, we replace $x$ with $6$ in the expression $7x - 4$. So we have:
$$f(6) = 7(6) - 4$$
3. Performing the multiplication
Now we perform the multiplication:
$$f(6) = 42 - 4$$
4. Subtracting to find the final value
Finally, we subtract to find the value of $f(6)$:
$$f(6) = 38$$
5. Final Answer
Therefore, $f(6) = 38$.
### Examples
In real life, this type of function can model various scenarios. For example, imagine a taxi service charges a fixed rate per mile, with an additional flat fee. If the rate is $7 per mile and the flat fee is $4 less than the total, the function $f(x) = 7x - 4$ can represent the total cost for a ride of $x$ miles. Evaluating $f(6)$ would then tell you the cost of a 6-mile ride. Understanding function evaluation is crucial for making predictions and decisions based on mathematical models.