1. {y=2
{3x-y=4
3x-2=4
x=2
(x;y) = (2,;2)
{2=2
{3*2-2=4
{2=2
{4=4
(x;y) = (2;2)
2. 6m2n-3m2+2mn-m
m(6mn-3m+2n+1)
m(3m(2n-1)+2n-1)
m(2n-1)(3m+1)
3. (2x-1)(2x+1)=2(x-3)2+x(2x-3)
4x2-1=2(x2-6x+9)+2x2-3x
4x2-1=2x2-12x+18+2x2-3
4x2-1=4x2-15x+18
-1x=-15x+18
15x=18+1
15x=19
x=19/15