The coefficient is a number before a variable.
Here, the coefficient is 9.
The like terms are any terms that have the same variable.
Here, 9k and -k are like terms, and 7 and 4 are like terms as well.
Combine like terms:
8k+3
The constants are: 7 and 4 (Constants are numbers in an expression or equation)
After combining like terms, the constant became
3