50%x +10%x+ 20%x +6=

50%x +10%x+ 20%x +6= 80%x=6 /:80 x=0,075

50%x +10%x+ 20%x +6= 0 80%x=-6 |/80% x=-7,5

50%x +10%x+ 20%x +6= 0 0,5x+0,1x+0,2x = -6 0,8x = -6 / :0,8 x = -7,5