Question 327945
1.{{{4b - c = -10}}}
2.{{{a - 2b = 5}}}
3.{{{3a + 4c = -11}}}
Eliminate one of the variables.
From eq. 2,
{{{a=2b+5}}}
Substitute into eq. 3,
{{{ 3(2b+5)+4c=-11}}}
{{{6b+15+4c=-11}}}
{{{6b+4c=-26}}}
4.{{{3b+2c=-13}}}
Multiply eq. 1 by (2) and add to eq. 4 to elminate c.
{{{8b-2c+3c+2c=-20-13}}}
{{{11b=-33}}}
{{{highlight(b=-3)}}}
Then from eq. 4,
{{{-9+2c=-13}}}
{{{2c=-4}}}
{{{highlight(c=-2)}}}
And finally from eq. 2,
{{{a=2(-3)+5}}}
{{{highlight(a=-1)}}}