a)
{3x - y = 8 /v*-1
{3x - y = -2
{-3x + y = -8
{ 3x - y = -2
0 = -10
b)
{2x - y = -2 / *6
{2x - 3y = 3 / *(-2)
{12x - 6y = -12
{ -4x + 6y = -6
8x = -18
x=2,25
c)
{ x - 7y = 3 / * -5
{ 5x - 2y = 11
{ -5x + 35y = -15
{ 5x - 2y = 11
33y=3
y=(3/33)
d)
{2x+ y = 4
{x - 2y = 7 /* -2
{2x + y = 4
{-2x + 2y = -14
3y=10
y=2,1
e)
{ 7x + 2y = -13 / *-3
{ 5x + 3y = -3 / *2
{-21x + (-6y)= 39
{ 10x + 6y = -6
-11x=33
x= -3
f)
{5x - y = 6 / *2
{ 3x + 2y = 1
{10x - 2y = 6
{ 3x + 2y = 1
13x=7
x=2,1