Step-by-step explanation:
first 3(-x+5) you distribut
then you would get 15-3x+15=21+6x and u combine like terms which is 3x and 6x which is 9 and u get 15-9x+15=21tthen u sabtract 15x on both side and get 15-9=21 then u subtract 15 ok both side and get x = 0.7
