A sleeping bag weighs 8 pounds. Your backpack and sleeping bag together weigh 31 pounds. Write an equation to determine whether the backpack without the sleeping bag weighs 25 or 23 pounds.
backpack+sleeping bag=31 b+sb=31 sb=8 b+8=31 subtract 8 from both sides b+8-8=31-8 b+0=23 b=23 backpack weighs 23 pounds with out sleeping bag equation is b+s=31 s=8