SOLUTION: solve the system by substitution. x + y = 12 y = 2x

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Question 110548: solve the system by substitution.
x + y = 12
y = 2x
Answer by HyperBrain(694) About Me  (Show Source):
You can put this solution on YOUR website!
x+%2B+y+=+12
But, y=2x. So,

x%2B%282x%29=12
x%2B2x=12
3x=12
3x%2F3=12%2F3
x%283%2F3%29=4
x%2A1=4
x=4

Again, y=2x So,
y=2%2A4=8

Thus, x=4 and y=8.

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HyperBrain!