SOLUTION: solve each system of equations by the substitution method 3y-x=6 4x+12y=0

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Question 999517: solve each system of equations by the substitution method
3y-x=6
4x+12y=0
Found 2 solutions by mananth, MathTherapy:
Answer by mananth(16946) (Show Source):
You can put this solution on YOUR website!

-1 x + 3 y = 6 .............1
3 y = 6 + 1 x
/ 3 =
y = 2 + 1/3 x
4 x + 12 y = 0 .....................2
Substitute y in (2)
4 x + 12 ( 2 + 1/3 x ) = 0
4 x + 24 + 4 x = 0
4 x 4 x = -24
8 x = -24
/ 8
x= -3
Plug the value of x in (1)
-1 x + 3 y = 6
-1 * -3 + 3 y = 6
3 + 3 y = 6
3 y = 3
/ 3
y= 1
m.ananth@hotmail.ca

Answer by MathTherapy(10552) (Show Source):
You can put this solution on YOUR website!

solve each system of equations by the substitution method
3y-x=6
4x+12y=0

3y - x = 6______3y - 6 = x -------- eq (i)
4x + 12y = 0 ------- eq (ii)
4(3y - 6) + 12y = 0 ------ Substituting 3y - 6 for x in eq (ii)
12y - 24 + 12y = 0
12y + 12y = 24
24y = 24
y = , or
3(1) - 6 = x ------ Substituting 1 for y in eq (i)
3 - 6 = x