re-arrange the first equation
z=3y+2X
now we can sub.(i.e substitute) Z in the other 2 equation
X-2y-4×(3y+2X)=14
[tex]x - 2y - 12y - 8x = 14[/tex]
[tex] - 7x - 14y = 14[/tex]
now divide both sides by 7
[tex]- x - 2y = 2[/tex]
we call this equation #1
3X+y -8×(3y+2X)=17
3X+y- 24y -16X=17
-13x -23y=17
we call this equation #2
now rearrange #1
x=-2-2y
sub. rearranged #1 into #2
-13(-2-2y) -23y =17
3x+26=17
x=-3
now sub. X in #1 or #2
-3=-2-2y
y=0.5
now sub both in one of the first equations
2x+3y=z
2×(-3)+3(0.5)=z
-6+1.5=-4.5=z
