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3 years ago

PLEASE HELP MEEEEEEEE :)))

Mathematics

2 answers:

Kay [80]3 years ago

8 0

Answer:

Step-by-step explanation:

Devaughn = 2x

Sydney = x

x + 2x = 78

3x = 78

x = 78 / 3

x = 26

Hope that helps!

Viktor [21]3 years ago

3 0

Answer:

Step-by-step explanation:

Lets say Devaughn age = d and Sydney age = s

Therefore,

d = 2s

and s + d = 78

Well, we can use substitution for d.

s + (2s) = 78

3s = 78

s = 26

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