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If DE = x + 9, EF = 9, and DF = 7x, what is DE?

If DE = x + 9, EF = 9, and DF = 7x, what is DE?-example-1

2 Answers

5 votes

Answer:

DE = 12

Explanation:

DF = DE + EF

7x = x+9 + 9

7x = x + 18

6x = 18

x = 3

DE = 3 + 9

DE = 12

User Eduardo Iglesias
by
7.8k points
2 votes

Answer: 12

Explanation:

x + 9 + 9 = 7x

9 + 9 = 6x

18 = 6x

x = 3

DE = x + 9 = 3 + 9 = 12 :>

User Jarnoan
by
7.2k points