you’re given:
-3(2x-3)= -6+9
you need to use distributive property and multiply -3 into 2x and -3:
-6x+9= -6+9
now you should simply the right side by adding 9 to -6:
-6x+9=3
then you need to subtract 9 from both sides in order to isolate the x term:
-6x= -6
then you divide both sides by -6 in order to get x by itself:
x=1