Respuesta :

pegah
first you should add +7 on both sides of the equation so you will have:
5k = -7 +7 ⇒ 5k = 0 so k = 0 :)))
i hope this is helpful 
have a nice day 
HaloMastet
so 5k-7=-7
You need to do the opposite of addition,which is subtraction so...
5k-7=-7
+7
__
K=0
and to double check it,replace the (or variable) with our answer (0)...
so
5×0-7=-7
solve the problem...and
-7=-7√