Question

2s + t = 7 ,\\ s-2t=1;

Answer 1

Ответ:

(3; 1)

Объяснение:

{2s + t = 7 | * 2

{s - 2t = 1

{4s + 2t = 14

{s - 2t = 1

{5s = 15

{4s + 2t = 14

1)

5s = 15

s = 15 : 5

s = 3

2)

4s + 2t = 14

4 * 3 + 2t = 14

12 + 2t = 14

2t = 14 - 12

2t = 2

t = 2 : 2

t = 1

Answer 2

{2s + t = 7 | * 2

{s - 2t = 1

{4s + 2t = 14

{s - 2t = 1

{5s = 15

{4s + 2t = 14

5s = 15

s = 3

4s + 2t = 14

4 * 3 + 2t = 14

12 + 2t = 14

2t = 14 - 12

2t = 2

t = 1

Відповідь: (3; 1)