Решите уровнение и сделайте проверку А) 5(x-2)-4x=-13 Б) 7х-0,9(10х+20)=4 В) 5+2(8-3х)-21=2

5(х-2)-4х=-13 5х-10-4х=-13 5х-4х=-13+10 х=-3 5(-3-2)-4*-3=-13 7х-0.9(10х+20)=4 7х-9х-18=4 7х-9х=4+18 -2х=22 х=22:-2 х=-11 7*-11-0.9(10*-11+20)=4 5+2(8-3х)-21=2 5+16-6х-21=2 -6х=2-5-16+21 -6х=2 х=2:-6 х=-0.333

1)5(x-2)-4x=-13, 5x-10-4x=-13, x=-13+10, x=-3 L(-3)=5(-3-2)-4.(-3)=5.(-5)+12=-25+12=-13 P(-3)=-13, L(-3)=P(-3) 2)7x-0,9(10x+20)=4, 7x-9x-18=4, -2x=4+18, -2x=22, x=-11 L(-11)=7.(-11)-0,9(-110+20)=-77-0,9.(-90)=-77+81=4 P(-11)=4, L(-11)=P(-11) 3)5+2(8-3x)-21=2, 5+16-6x-21=2,21-6x-21=2,-6x=2, x=-1/3 L(-1/3)=5+2(8+1)-21=5+2.9-21=5+18-21=23-21=2 P(-1/3)=2, L(-1/3)=P(-1/3)