To solve for \( f(x) \), we need to evaluate the function for a given value of \( x \). The function involves a square root and a linear transformation. We will substitute the value of \( x \) into the function and compute the result.
Step 1: Define the Function
The function given is \( f(x) = 5 \sqrt{8 - 7x} + 10 \). We need to evaluate this function for a specific value of \( x \).
Step 2: Substitute the Value of \( x \)
Substitute \( x = 1 \) into the function:
\[
f(1) = 5 \sqrt{8 - 7 \times 1} + 10
\]
Step 3: Simplify the Expression
Calculate the expression inside the square root:
\[
8 - 7 \times 1 = 1
\]
Thus, the function becomes:
\[
f(1) = 5 \sqrt{1} + 10
\]
Step 4: Evaluate the Square Root
Since \(\sqrt{1} = 1\), the expression simplifies to:
\[
f(1) = 5 \times 1 + 10
\]
Step 5: Calculate the Final Result
Perform the multiplication and addition:
\[
f(1) = 5 + 10 = 15
\]
Final Answer
The value of the function at \( x = 1 \) is \(\boxed{15}\).