1+2(7+9x)=7x-9 -5+3(-1-2x)=--x+4 2+9(8-3x)=--7x+4 5+4(9+x)=8x+2 7+5(2+x)=4x--3 --'это минус

1) 1 + 2(7 + 9x) = 7x - 9;1 + 14 + 18х - 7х + 9 = 0;24 + 11 х = 0;24 = - 11х;х = - 24/11 = - 2 2/11;2) -5 + 3(-1 - 2x) = -x + 4;-5 + (-3) - 6х +х - 4 = 0;- 12 - 5х = 0;- 5х = 12;х = - 12/5 = - 2 2/5;3) 2 + 9(8 - 3x) = -7x + 4;2 + 72 - 27х + 7х - 4 = 0;70 - 20х = 0;- 20х = -70;х = 70/20 = 3 1/2;4) 5 + 4(9 + x) = 8x + 2;5 + 36 + 4х - 8х - 2 = 0;39 - 4х = 0;4х = 39;х = 39/4 = 9 3/4;5) 7 + 5(2 + x) = 4x - (-3);7 + 10 + 5х - 4х + (-3) = 0;14 + х = 0;х = - 14.