A coefficient is just a number directly next to a variable. A constant is also a number but without any variables.When they say "like terms in math", you are just pairing the coefficients together and the variables (letters together).
For example:
4b+7b+5
B is a variable (letter). And 4b and 5b are like terms because they both have the variable 'b'. 5 has no like term because it is the only constant.
Your answer would be 11b+5.
Because you will add "like terms", 4b and 7b both have the same variable and they both have coefficients which are 4 and 7 so, I simply added them to get 11b.
