6/a) 10·(x-3,3)=77 => 10x - 33=77 => 10x=77+33 => 10x= 110 => x=110/10 => x=11
b) 4,2·(x+1,5)=8,4 => 4,2x + 6,3=8,4 => 4,2x=8,4-6,3 => 4,2x=2,1 => x=2,1/4,2 =>x=0,5
c) 1,5+x≤5/2 => x≤5/2 -15/10 => x≤25-15/10 =>x≤1 => x∈(-∞ ;1]
d) 1,1·x-1≤1,2 => 1,1·x≤1,2+1 =>1,1·x≤ 2,2 =>x≤2,2/1,1=>x≤2 => x∈(-∞ ;2]
