Question 773861
BC=4 and AC=8 - AB
AB < BC + AC (since any side is less than the sum of the other 2 sides)
AB < 4 + 8 - AB (since BC = 4, and AC = 8 - AB)
AB < 12 - AB 
Moving AB to the left side
2*AB < 12
{{{highlight(AB < 6)}}}
What we can conclude about AB is that it has to be less than 6.
Hope you got it :)