SOLUTION: y-x=3x 2(x+y)=14-y 3a+6b=-15 a=-2b-5 pls. solve by substitution

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Question 579893: y-x=3x
2(x+y)=14-y

3a+6b=-15
a=-2b-5
pls. solve by substitution
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
y-x=3x
add x to both sides
y= 4x

2(x+y)=14-y
substitute y
2(x+4x)=14+3x
10x=14+3x
add -3x to both sides
7x=14
/7
x=2
when x =2 y = 4x = 4*2=8
(2,8)