Chapter 1 - Foundations for Algebra - 1-8 An Introduction to Equations - Practice and Problem-Solving Exercises - Page 56: 26

$9(6+x)=1$

It asks for $9$ multiplied by the sum of $6$ and $x$. The sum of $6$ and $x$ is equal to $(6+x)$. Since you want to find the product of the sum and $9$, you will get $9(6+x)$. You are also told that the product is equal to one, so your final equation will be: $9(6+x)=1$