Answer:
-3x + (-7)
Step-by-step explanation:
First you want to find the like terms, in this case it is the numbers without a coefficient, (6 and -1). So you are then left with -6+(-1) which equals to -6-1 = -7. Finally, you combine the number with the coefficient (-3x) with the number without it (-7) and you get -3x-7
