I'm not sure what you mean by "which property should be used next"
but here's how you solve the problem
3x+2+3=7(x-1)-4
» 3x+5=7x-7-4 (I'm guessing that the property that will be used is expansion of 7(x-1) )
» 3x-7x=7-4-5
» -4x=-2
» x=(-2)/(-4)
» x=0.5