Question 256370
1.{{{ 3x - y = 0}}}
2.{{{4x + 2y = 1 }}}
Multiply eq. 1 by 2 and add to eq. 2.
{{{6x-2y+4x+2y=0+1}}}
{{{10x=1}}}
{{{x=1/10}}}
From eq. 1,
{{{3(1/10)-y=0}}}
{{{y=3/10}}}
.
.
.
3. {{{8x + 4y = 2}}}
4.{{{  y = -2x + 1}}}
Substitute for y in eq. 3 using eq. 4,
{{{8x + 4y = 2}}}
{{{8x + 4(-2x+1) = 2}}}
{{{8x-8x+4=2}}}
{{{4=2}}}
Inconsistent results means the two lines are parallel, no solution.