Answer:
The value of the expression c-2 when c=7 is 5.
Explanation:
Consider the provided expression.
We need to find the value of expression for c=7. 
Substitute the value of c=7 in the provided expression and simplify as shown. 
 
 
 
 
Subtract the numbers as shown:
 
 
Hence, the value of the expression c-2 when c=7 is 5.