Question

A scuba diver swam 96 feet beneath the surface of the lake. He then climbs up 49 feet. What is his depth now? Please explain and show work

Answer 1

That's 96 feet DOWN from the lake surface, and then 49 feet towards the surface.  His depth would be -96+49 feet, or -47 feet, where the surface would be 0 feet, down is negative and up is positive.

Answer 2

0 = Surface level

Beneath means subtraction.
0 - 96 = -96

Climbs means addition.

-96 + 49 = -47

The scuba diver is -47 feet beneath the surface of the lake.