The correct answer would be: C. 2(n-5)=26
For this case the 'number' is represented at 'n'.
the number (n) is decreased by 5 which would show as: (n-5)
The result of (n-5) is then multiplied by 2. Therefore, 2(n-5) looks like this since the 2 would multiply into the parenthesis.
Then you would add =26 at the end since that would be the results.
2(n-5)=26 would be your answer.
Hope this helps! :3
