x,y,z are te numbers
x+y+z=24
let's say x is smalest and z is biggest
2x=z-2
z=x+y
nice
so we got
x+y+z=24
so subsitute z for x+y
z+z=24
2z=24
divide both sides by 2
z=12
sub back
2x=z-2
2x=12-2
2x=10
divide by 2
x=5
sub back
z=x+y
12=5+y
minus 5 both sides
7=y
the numbers are
5,7,12