найдите корни уравнения:1)-0,5х+13,8=12,4;2)х÷(-3)-20,1=-21,9;3)2,5÷х+2,812=-7,188;4)-91,2+(-2х)=-100,7.

1)-0.5x+13.8=12.4-0.5x=12.4-13.8=-1.5x=-1.5:-0.5x=32) x÷(-3)-20.1=-21.9x÷(-3)=-21.9+20.1=-1.8x=-3×-1.8=5.43) 2.5÷x+2.812=-7.1882.5=x=-10x=-44) -91.2+(-2x)=-100.7-2x=-91.2+100.7=9.5x=9.5:-2=-4.75