Question

X,y dan z adalah penyelesaian dari sistem persamaan

x + 2y = -4
2x + z = 5
y + 3z = -6

Tentukan nilai x,y,z

Answer 1

X + 2y = - 4 ..kalikan 2
2x + z = 5.
.
2x + 4y = -8
2x + z = 5
kurangkan
4y - z = - 13
atau z = 4y + 13 sub ke y + 3z =  - 6
y + 3(4y+13) = -6
y + 12y + 39 = -6
13y = -45
y = - 45/13

z= 4y + 13 = - 11/13

x = -4 - 2y = 38/13

Answer 2

X= -4-2y 2x+z=5 2 (-4-2y)+z=5 -8-4y+z=5 Z= 13+4y Y+3z=-6 Y+ 3(13+4y)=-6 Y+ 39+12y=-6 13y= -6-39 13y=-45 Y=-45/13 Z= 13+4y=13+4.(-45/13)=13+ (-180/13)= 169/13-180/13= -11/13 X=-4-2y=-4-2(-45/13)= -4-(-90/13)=-4+90/13= -52/13+90/13= 38/13 X=38/13 Y=-45/13 Z=-11/13