Hello there! The answers are -2x and -5x.
Like terms are terms that have the same x values and exponential values. Out of the options you have provided, the only terms that have like terms are -2x and -5x since they both have a value of x to the first power. 2 and 6x^2 both have different exponential values of x, so they are not like terms.
I hope this helps and have a great rest of your day!
