SOLUTION: 4x-12y=5 -x+3y=-1 solve by substitution tried it like this 4(3y-1)=5 but it was not comming out right

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Question 108675: 4x-12y=5
-x+3y=-1
solve by substitution
tried it like this 4(3y-1)=5 but it was not comming out right

Found 3 solutions by scott8148, edjones, Earlsdon:
Answer by scott8148(6628)   (Show Source):
You can put this solution on YOUR website!
x=3y+1 (note sign change) ... you substituted ok by what happened to the -12y?

Answer by edjones(8007)   (Show Source):
You can put this solution on YOUR website!
A) 4x-12y=5
B) -x+3y=-1
.
B)-x+3y-3y=-3y-1
-x=-3y-1
x=3y+1 multiply -1 times each side.
.
A) 4(3y+1)-12y=5
12y+4-12y=5
4=5 There is no answer to this system.
.
Here is a graph of the system.
The lines are parallel; they have the same slope.
.
Ed

Answer by Earlsdon(6294)   (Show Source):
You can put this solution on YOUR website!
Solve by substitution:
4x-12y = 5
-x+3y = -1 Solve this for x:
x = 3y+1 and substitute into the 1st equation.
4(3y+1)-12y = 5 Simplify and solve for y.
12y+4-12y = 5 Combine like terms.
(12y-12y)+4 = 5
4 = 5 NO WAY! The equations are inconsistent !
This means that there no value of x or y that will work, or there is no solution. The lines represented by these two equations are parallel and, since they don't intersect, there is no solution.