Question

Metodo de sustitucion:
-4x+3y=-2
Y=x-1

12x-5y=-20
Y-x=4

8x+5y=24
Y=-4x

-7x-6y=4
X+3y=8

Es urgente ​

Answer 1

Respuesta:

$a)-4x+3y=-2 \\ </p><p>Y=x-1 \\ - 4x + 3(x - 1) = - 2 \\ - 4x + 3x - 3 = - 2 \\ - x = 1 \\ x = - 1 \\ y = ( - 1) - 1 \\ y = - 2 \\ b)12x-5y=-20 \\ </p><p>Y-x=4 \\ y = 4 + x \\ 12x - 5(4 + x) = - 20 \\ 12x - 20 - 5x = - 20 \\ 7x = - 20 + 20 \\ 7x = 0 \\ x = 0 \\ y = 4 + 0 \\ y = 4 \\ c)8x+5y=24 \\ </p><p>Y=-4x \\ 8x + 5( - 4x) = 24 \\ 8x - 20x = 24 \\ - 12x = 24 \\ x = \frac{24}{ - 12} \\ x = - 2 \\ y = - 4( - 2) \\ y = 8 \\ d)-7x-6y=4 \\ </p><p>X+3y=8 \\ x = 8 - 3y \\ - 7(8 - 3y) - 6y = 4 \\ - 56 + 21y - 6y = 4 \\ - 56 + 15y = 4 \\ 15y = 4 + 56 \\ 15y = 60 \\ y = \frac{60}{15} \\ y = 4 \\ x = 8 - 3(4) \\ x = 8 - 12 \\ x = - 4$