Question

х - у = 2
{3х - у = 5

{4х - у = 5
{3х + 2у = 12
1
- -
{2 у+ 2х= 6
{4х + у = 12

{ х - у = - 2
{3х - 3у = 6 ​

Answer 1

1. 2.
{у=-5+4х
{у=-2+2х. {3х+2у=12
{3х-у=5. 3х+2(-5+4х)=12
3х-(-2+2х)=5. х=2
Х=3. у=-5+4•2
У=-2+2•3. у=3
У=4. (х,у)=(2,3)
(Х,У)=(3,4). {4•2-3=5
{2•3-4=2. {3•2+2•3=12
{3•3-4=5. {5=5
{2=2. {12=12
{5=5. (х,у)=(2,3)
(Х,У)=(3,4).

3.
{2у+2х=6
{у=12-4х
2(12-4х)+2х=6
х=3
у=12-4•3
у=0
(х,у)=(3,0)
{2•0+2•3=6
{4•3+0=12
{6=6
{12=12
(х,у)=(3,0)

4.