Step-by-step explanation:
Add 3y to both sides
6x-3y- 15 + 3y =0+3y
Simplify
6x- 15 =3y
Add 15 to both sides
6x-15 + 15 =3y + 15
6x =3y+ 15
Divide both sides by6
6x/6= 3y/6+ 15/6
x=y+5/2
