so 36+2x=3y
-x+y=z
z/2=8
(y-x)/2=8
first you want to find what x or y is by isolating one of them
so (y-x)/2=8
multiply both sides by 2
y-x=16
subtract 16 from both sides
y-x-16=0
add x to both sides
y-16=x
subtitute into first equation
36+2(y-16)=3y
distrubute
36+2y-32=3y
add like terms
4+2y=3y
subtract 2y from both sides
4=y
subutue into second equation
(4-x)/2=8
multiply both sides by 2
4-x=16
add x to both sides
4=16+x
subtract 16 from both sides
-12=x
y=4
