Answer:
Variables: you are correct
Coefficients: -2
Constant: 3/7
Explanation:
Variables are letters used in math so you were correct.
Coefficients are numbers with a variable. So to find the coefficient you would look for a number "connected" to a variable. This would be -2 because it is being subtracted from the first term.
The constant is 3/7 because you could put it on a number line.