The number that is halfway between to others is their average value, that is, their sum divided by 2.
(6 +24)/2 = 30/2 = 15
15 is halfway between 6 and 24.
Add 7 to both sides.
-3y = 9
Divide -3 on both sides.
y = -3
Hope this helps!
Sorry I need to answer something so I can ask questions so I’m typing this
