# Prealgebra

Solve by substitution:
x+y=9
y=2x

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asked by Jillian
1. x+y=9 2x=4 because 2x2=4
y=2x

x+2x=9
x+4=9
-4 -4
x=5
x+y=9
chick answer by 5+4=9

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posted by Dj

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