Question

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.

Answer 1

sleeping bag weights 8 pounds
sb=8

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