1463.
Решите системы уравнений:​

Пошаговое объяснение:

1.

{3х+5у=16 /*-2

2х+3у+9/*3

{-6х-10у=-32

6х+9у=27

{-6х-10у+6х=9у=-32+27

6х+9у=27

{-у=-5

6х+9у=27

{у=5

6х=-45+27

{у=5

х=-18/6

[у=5

х=-3

2.

9х-7у=95

4х+у=34

{9х-7у=95

у=34-4х

{9х-7(34-4х)=95

у=34-4х

{9х-238+28х=95

у=34-4х

{37х=333

у=34-4х

{х=333/37

у=34-4х

{х=9

у=34-4*9

{х=9

у=-2

3.

3х-5у=23 /*3

2х+3у=9/*5

[9х-15у=69

10х+15у=45

{9х-15у+10х+15у=69+45

10х+15у=45

{19х=114

10х+15у=45

{х=6

2*6+3у=9

{х=6

3у=-3

{х=6

у=-1

4.

6х+5у=0

2х+3у=-8 /*-3

{6х+5у=0

-6х-9у=24

{6х+5у-6х-9у=24

6х+5у=0

{-4у=24

6х+5у=0

{у=-6

6х-30=0

{у=-6

х=30/6

{у=-6

х=5