Question 248537
what are all the possible lengths 'x' of the third side of a triangle if the other two sides have lengths of 3 and 20 ? 
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20-3 < x < 20+3
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17 < x < 23
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Why?  If the 3 is colinear to the left you get a straight segment 3+20
If the 3 is colinear to the right you get a staight segment 20-3
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Draw the picture and you will see what I mean.
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Cheers,
Stan