Поиогите алгебра 7 класс

5x - 7y = -24
x = -3y + 4

-15y + 20 - 7y = -24
x = -3y + 4

-22y = -44
x = -3y + 4

y = 2
x = -2

===

2x + 5y = -8
2x + 3y = -4

2у = -4
у = -2

2х - 10 = -8
2х = 2
х = 1

2 + 3у = -4
3у = -6
у = -2

х = 1
у = -2

====

-3x + 7y = 29
6x+5y = 13

6x - 14y = -58
6x + 5y = 13

-19y = - 71
y = 3 14/19

-3x + 26 3/19 = 29
-3x = 2 16/19
x = -18/19

x = -18/19
y = 3 14/19

=====

3x + 7y = -5
5x + 4y = 7

-15x - 35y = 25
15x + 12y = 21

-23y = 46
y = -2

5x - 8 = 7
5x = 15
x = 3

x = 3
y = -2

====

x+y/2 + x-y/3 = 6
x+y/4 - x-y/3 = 6

3x+3y+2x-2y/6 = 6
3x+3y-4x+4y/12 = 6

5x+y = 36
-x+7y = 72

y = 36 - 5x
-x + 252 - 35x = 72

y = 36 - 5x
-36x = -180

y = 36 - 25
x = 5

y = 11
x = 5

1)a) x=2 ; y=9