Question

-(1,9а-8,9б)+(0,5-б-7,1а)-(1,4б-3,9а) помогите

Answer 1

-(1,9a-8,9b)+(0,5-b-7,1a)-(1,4b-3,9a)=-1,9a+8,9b-0,5-b-7,1a-1,4b-3,9a=-5,1a+6,5b+0,5