Answer:
Step-by-step explanation:
Note: 3x + 8 is incorrect as leads to negative value for the length. Therefore changed to 3x - 8
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- DE is midsegment
- Midsegment = 1/2 Base as per definition, DE = 1/2AC
Substitute values
- 3x - 8 = 1/2(4x + 10)
- 3x - 8 = 2x + 5
- 3x - 2x = 5 + 8
- x = 13
DE = 3*13 - 8 = 31
