Question

15:[11-(7x5-9x9:x:3):8+2x4]x3=3 Aflati-l pe x

Answer 1

15:[11-(7x5-9x9:x:3):8+2x4]x3=3/:3
15:[11-(7x5-9x9:x:3):8+2x4]=1/x[11-(7x5-9x9:x:3):8+2x4]
11-(7x5-9x9:x:3):8+2x4=15/-11
-(35-81:x:3):8+8=4/-8
-(35-81:x:3):8=-4/x(-1)
(35-81:x:3):8=4/x8
35-81:x:3=32/-35
-81:x:3=-3/x(-1)
81:x:3=3/x3
81:x=9
81=9x/:9
x=9