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2 years ago

If DF = 170, find the value of x. Then find DE and EF. DE=3x + 20 EF=2x + 40

Mathematics

1 answer:

Julli [10]2 years ago

7 0

9514 1404 393

Answer:

DE = 86

EF = 84

Step-by-step explanation:

We assume that point E lies on segment DF, so that ...

DE + EF = DF

(3x +20) +(2x +40) = 170

5x = 110 . . . . . . . . . . . . . . . collect terms, subtract 60

x = 22 . . . . . . . . . . . . divide by 5

DE = 3×22 +20 = 66 +20 = 86

EF = 2×22 +40 = 44 +40 = 84

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