Answer: 30
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Step-by-step explanation:
The given triangle has sides of 10, 14, and 18. We see that 18 is the longest side. It corresponds to the longest side of the second triangle, which is 54 units.
The scale factor is 54/18 = 3. Meaning that the second triangle's side lengths are three times longer than the side lengths of the first triangle.
From that, we can say the shortest side of the second triangle is 3*10 = 30 units.
Put another way, the {10,14,18} becomes {30,42,54} when we triple each value in the first set.