Answer:
perimeter is doubled to 30.8 cm
Explanation:
The perimeter is the sum of side lengths. The perimeter of this figure is the sum ...
4 cm + 5 cm + 6.4 cm = 15.4 cm
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When the side lengths are doubled, the perimeter is doubled:
2(4 cm) +2(5 cm) +2(6.4 cm) = 2(4 cm +5 cm +6.4 cm) = 2(15.4 cm)
= 30.8 cm
The perimeter is doubled.
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Additional comment
Any scale factor that applies to all of the side lengths also applies to the perimeter.