when a ship was sinking, some sailors threw a valuable treasure chest overboard. The deck of the ship was 46 ft above the water's surface. The chest sank to a depth o f387 feet (-387). write an solve a subtraction equation to find the difference between the two locations.
The difference between the two locations will be the original location (the deck of the ship) minus the final location (the bottom of the ocean). So . . .
difference = ship - bottom = 46 ft - (-387 ft)
If you need to write this with all symbols, choose a letter for each value, say "s" for ship deck, "b" for ocean bottom and "d" for the difference. Then,
d = s - b = 46 ft - (-387 ft) = 46 ft + (+387 ft) = 46 ft + 387 ft = 433 ft
The tricky part is remembering that when you subtract a negative number, there are two minus/negative signs next to each other. You can turn both of them into + signs.