Răspuns :
18:[(5*5-5x)*2-11]=2
(25-5x)*2-11=18:2
50-10x=9+11
-10x=20-50
-10x=-30 (-1)
x=30:10
x=3
(25-5x)*2-11=18:2
50-10x=9+11
-10x=20-50
-10x=-30 (-1)
x=30:10
x=3