Question

X+2Y=9
2X+Y=10
me ajudem resposta com cálculos

Answer 1

{ X+2Y  = 9 (-2)
{2X+ Y =10

{-2X - 4Y = -18
{ 2X +  Y =   10
 ////// - 3Y = - 8 
          3Y =  8 --> Y = 8/3
X+2Y = 9
X +2(8/3) = 9
X + 16/3 = 9
X = 9 - 16/3 ----> X = 11/3

   S= (11/3 , 8/3)

Answer 2

x+2y=9
2x+y=10          *(-2)

x+2y=9
-4x-2y=-20

-3x=-11
x=11/3

11/3+2y=9  tire o mmc

11+6y=27
6y=27-11
6y=16
y=16/6

se simplificar 16/6=8/3