Question 371449
1.{{{4x+2y=8}}}
2.{{{y=-2x+4}}}
Substitute eq. 2 into eq. 1,
{{{4x+2(-2x+4)=8}}}
{{{4x-4x+8=8}}}
{{{8=8}}}
True.
These two equations are actually the same equation. 
There are an infinite number of solutions.