Question 147794
1.{{{x+3y=12}}}
2.{{{4x-y=-17}}} 
You didn't specify a method.
We'll use substitution.
Solve eq.1 for x in terms of y.
1.{{{x+3y=12}}}
{{{x=12-3y}}}
Now substitute this into eq. 2 and solve for y.
2.{{{4x-y=-17}}} 
{{{4(12-3y)-y=-17}}} 
{{{48-12y-y=-17}}} 
{{{48-13y=-17}}} 
{{{-13y=-65}}}
{{{y=5}}}
From eq. 1,
{{{x=12-3y}}}
{{{x=12-3(5)}}}
{{{x=12-15}}}
{{{x=-3}}}
The solution is x=-3 and y=5, also shown graphically.
{{{ graph( 300, 300, -5, 5, -2, 8, 4x+17, (12-x)/3) }}}