Answer:
a. 1.6 feet
Explanation:
The triangle inequality requires the sum of the shortest two sides exceed the longest side. If x represents the shortest side, that means ...
x + 3.1 > 4.6
x > 1.5 . . . . . . . subtract 3.1
The smallest answer choice meeting this requirement is 1.6 feet.
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Comment on this answer
A measure of 1.5001 feet will satisfy the triangle inequality. That value would round to 1.5 when rounded to the nearest tenth.