Question

AIUDAAA es para HOY si NO sabes la respuesta... por favor NO contestes de verdad necesito ayuda

RESOLVER SOLO POR EL METODO DE SUSTITUCION



2X + Y= 1
6X +3Y=3

X + Y= 5
2X + Y=9

6X + Y=-4
X – Y=-14

7X + Y = -1
X + 2Y =4

Answer 1

Respuesta:

1)

{ 2x + y = 1

{ 6x + 3y = 3

=====> * 2x + y = 1 =====> y = 1 - 2x

===> 6x + 3y = 3 ===> 6x + 3 (1 - 2x) = 3

===> 6x + 3 - 6x = 3 ===> 0x = 3 - 3 ===> 0x = 0

Rpta: Es compatible indeterminado.

2)

{ x + y = 5

{ 2x + y = 9

===> * x + y = 5 ===> y = 5 - x

===> 2x + y = 9 ===> 2x + (5 - x) = 9

===> x + 5 = 9 ===> x = 9 - 5 ===> x = 4

===> x + y = 5 ===> 4 + y = 5 ===> y = 5 - 4 ===> y = 1

Rpta: x = 4 ; y = 1

3)

{ 6x + y = -4

{ x - y = -14

===> * 6x + y = -4 ===> y = -4 - 6x

===> x - y = -14 ===> x - (-4 - 6x) = -14 ===> x + 4 + 6x = -14

===> 7x = -14 - 4 ===> 7x = -18 ===> x = -18/7

===> 6x + y = -4 ===> 6 (-18/7) + y = -4

===> -108/7 + y = -4 ===> y = -28/7 + 108/7 ===> y = 80/7

Rpta: x = -18/7 ; y = 80/7

4)

{ 7x + y = -1

{ x + 2y = 4

===> * 7x + y = -1 ===> y = -1 - 7x

===> x + 2y = 4 ===> x + 2 (-1 - 7x) = 4 ===> x - 2 - 14x = 4

===> -13x = 4 + 2 ===> -13x = 6 ===> x = -6/13

===> 7x + y = -1 ===> 7 (-6/13) + y = -1

===> -42/13 + y = -1 ===> y = -13/13 + 42/13 ===> y = 29/13

Rpta: x = -6/13 ; y = 29/13

5)

{ -10x - 5y = 0

{ 21x - 7y = 28

===> * -10x - 5y = 0 ===> -5y = 10x ===> y = -2x

===> 21x - 7y = 28 ===> 21x - 7 (-2x) = 28

===> 21x + 14x = 28 ===> 35x = 28 ===> x = 28/35 ===> x = 4/5

===> -10x - 5y = 0 ===> -10 (4/5) - 5y = 0 ===> -40/5 - 5y = 0

===> -8 - 5y = 0 ===> -5y = 8 ===> y = 8 ÷ -5 ===> y = -8/5

Rpta: x = 4/5 ; y = -8/5

Espero que te ayude...