Question 896909
The sum of the lengths of any two sides of a triangle is greater than
 the length of the third side. 
In triangle ABC, BC = 4 and AC = 8-AB . 
What can you conclude about AB?
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Using the fact stated above you get:
BC + AC > AB
4 + 8-AB > AB
Adding AB to both sides you get:
12 > 2*AB
Then AB < 6
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Also 4 + AB > 8-AB
Then 2AB > 4
AB > 2
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Putting those together you get:
2 < AB < 6
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Cheers,
Stan H.
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