SOLUTION: Solve the system by graphing. x+2y=4 x+2y=-2

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Question 68286: Solve the system by graphing.
x+2y=4
x+2y=-2

Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
Solve the system by graphing.
x+2y=4
x+2y=-2
Because these lines have the same coefficients for x and y and different constants we know they are parallel and therefore never intersect.
However, let's graph them anyways.
:
For x+2y=4
let x=0 and solve for y:
0+2y=4
2y=4
2y/2=4/2
y=2
Plot (0,2)
Now let y=0 and solve for x:
x+2(0)=4
x+0=4
x=4
Plot (4,0)
Connect the two points and you have this line:
graph%28300%2C200%2C-10%2C10%2C-10%2C10%2C%28-x%2B4%29%2F2%29
For x+2y=-2
Let x=0 and solve for y:
0+2y=-2
2y=-2
2y/2=-2/2
y=-1
Plot (0,-1)
Now let y=0 and solve for x:
x+2(0)=-2
x+0=-2
x=-2
Plot (-2,0)
Connect the two points and you have a second line:
graph%28300%2C200%2C-10%2C10%2C-10%2C10%2C%28-x%2B4%29%2F2%2C%28-x-2%29%2F2%29
The line are parallel and will never intersect to give you a solution, therefore, there is no solution.
Happy Calculating!!!