Question

Hola buenas a todos si me pudieran ayudar con estos ejercicios se los agradeceria mucho a) 5x +2y = 1 −3x +3y = 5 b) 5x − y = 3 −2x + 4y = −12 c) −2x +3y = 14 3x − y = –14 d) x +2y = 1 –3x + y = –10

Answer 1

Respuesta:

a)

5x + 2y = 1- 3x + 3y = 5

5x + 2y = 5

1 - 3x + 3y = 5

...

5x + 2y = 5

- 3 + 3y = 4

...

15x + 6y = 15

-15x + 15y = 20

= 21y = 35

y = 5/3

- 3x + 3 x 5/3 = 4

x= 1/3

(x, y) = (1/3, 5/3)

5 x 1/3 + 2 x 5/3 = 1 - 3 x 1/3 + 3 x 5/3 = 5

5 = 5 = 5

(x, y) = (1/3, 5/3)

b)

5x − y = 3 −2x + 4y = −12

...

5x -y = -12

3- 2x + 4y = -12

...

5x - y = -12

- 2x + 4y = -15

...

20x - 4y = -48

- 2x + 4y = -15

= 18x = -63

x = - 7/2

5x (- 7/2) - y = -12

y = - 11/2

(x, y) = (- 7/2, - 11/2)

5 x (- 7/2) - (- 11/2) = 3 - 2 x (- 7/2) + 4 x (- 11/2) = -12

-12 = -12 = -12

(x, y) = (- 7/2, - 11/2