Question

Proszę o rozwiązanie dwóch układów równań :

-x - y = 2

2(3x + y) = -20

4x + 3y = 54

1/3x = 4 (1 + 1/8y)

Answer 1

-x - y = 2

2(3x + y) = -20

 

-x - y = 2        |*2

6x + 2y = -20

 

-2x - 2y = 4

6x + 2y = -20

_________________

4x = -16

x = -4

 

-(-4)- y = 2

4 - y = 2

-y = -2

y = 2

 

x=-4

y=2

 

4x + 3y = 54

1/3x = 4 (1 + 1/8y) 

 

4x + 3y = 54

1/3x = 4 + 1/2y  |*6

 

4x +3y = 54

2x = 24 + 3y

 

4x + 3y = 54

2x - 3y = -24

_______________

6x = 30

x = 5 

 

2*5 - 3y = -24

10 - 3y = -24

-3y = -34

y = 11⅓

 

x = 5

y=11⅓