Упрасти выражение: 1) -2/5(15а+1/2б)+1/5б; 4 2/5(3/11-а)-1 1/5; -1/9(3б-9)+1/3б; -2 3/8(4с+7/19)+8 1/2с
1) -2/5(15а+1/2б)+1/5б = -2*3*а-1/5б+1/5*б=-6*а-2/5б 2) 4 2/5(3/11-а)-1 1/5 = 22/5(3/11-а)-6/5=6/5-22/5*а-6/5=-22/5*а 3) -2 3/8(4с+7/19)+8 1/2с = -19/8(4*с+7/19)+17/2*с=-19/2*с-7/8+17/2*с=-с-7/8