Answer:
2.1
Step-by-step explanation:
Multiplying the smaller triangle's side lengths by the scale factor will give you the side lengths of the larger triangle. Similarly, dividing the larger triangle's side lengths by the scale factor will give you the side lengths of the smaller triangle.
4.2 * 1/2 =
2.1
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check
2.1 : 1/2 =
8.4 * 1/2
4.2
the answer is good
