9514 1404 393
Answer:
Chun is correct
Explanation:
The angle bisector divides the sides of the triangle proportionally. Any proportion that is written should equate ratios of corresponding sides.
Chun's proportion correctly relates the top-side measures to their corresponding bottom-side measures:
top short : bottom short = top long : bottom long
5 / 8 = 15 / x
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Traci's error is that she mixes top-side and bottom-side measures. Her incorrect relation is ...
top short : bottom long = bottom short : top long
She has used top:bottom for short measures and bottom:top for long measures. This mixing will give Traci an incorrect solution.
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Chun's proportion correctly gives x=24.