Answer :

AL2006
This is a very interesting equation.

Remember:     The "solution" to the equation is the number that  ' k '  must be
in order to make the equation a true statement.

-3k  =  -5k

Divide each side of the equation by  ' k '  .
Then you have
                               -3  =  -5 .

Is there ANY value for ' k ' that can make that a true statement ?

I don't think so.

This equation has NO solution.