Question

{ 2x +8y = 0 { 9x +6y =15

Ajudem pfv?

Answer 1

{2x + 8y = 0
{9x + 6y = 15
===========
2x = -8y
x = -8y/2

9x + 6y = 15
9x = 15 - 6y
x = 15 - 6y/9


x = x


$\frac{ - 8y}{2} = \frac{15 - 6y}{9} \\ \\ 30 - 12y = - 72y \\ - 12y + 72y = - 30 \\ 60y = - 30 \\ y = \frac{ - 30}{60} \\ y = - 0.5$


x = -8y/2
x = -8.(-0,5)/2
x = 4/2
x = 2


S={ 2, -0,5 }