1) 7x+36=6x+72 7x-6x=72-36 x=36 2)3x+x=6x-48 4x-6x=-48 2x=48 x=24 3)5,1-8x=3,3-10x 2x=-1,8 x=-0,9 4) 1,4-2,1y=-7 -2,1y=-8,4 y=4