Question 58611
Hi Sher,  
  Solve the following systems by graphing:

L1)   2x - y = 4
L2)   2x - y = 6

 This system is parallel and has no solution, the two lines will never intersect.
:
For L1) let x=0 and solve for y:
2(0)-y=4
0-y=4
-y=4
-(-y)=-4
y=-4  Plot (0,-4)
Now let x=1 and solve for y:
2(1)-y=4
2-y=4
-2+2-y=4-2
0-y=2
-y=2
-(-y)=-2
y=-2  Plot (1,-2)  Connect the points and you have this line:
{{{graph(300,200,-10,10,-10,10,-(-2x+4))}}}
:
For L2)  Let x=0 and solve for y:
2(0)-y=6
0-y=6
-y=6
-(-y)=-6
y=-6
Plot (0,-6)
Now let x=1 and solve for y:
2(1)-y=6
2-y=6
-2+2-y=6-2
0-y=4
-y=4
-(-y)=-4
y=-4
Plot (1,-4)
Connect the dots and you have a second line:
{{{graph(300,200,-10,10,-10,10,-(-2x+4),-(-2x+6))}}}
See the lines are parallel and they will never intersect.
Happy Calculating!!!