2x+3y-4z=0 (1)3x+4y+5z=0 (2)2(2)-3(1)-y+18z=0y=18zfrom (1)2x+54z-4z=0x=-25zx:y:z = 25 : -18: -1x=25k , y=-18k ,z=-k(x+y+z)/(x-y+z)=(25-18-1)/(25+18-1)=6/42=1/7
