-6r + 12 -8r = -2

 

Rewrite it as -14r +12 =  -2 .  Now  Subtract 12 from both sides

 

                             -12      -12

                      ___________________

 

                       -14r = -14

 

Now divide both sides by -14 , to get  r =1     Answer

 

                                                       *****