What is the value of the expression x + (–y) when x = –3.8 and y = 1.7?
a. –5.5
b. –2.1
c. 2.1
d. 5.5

a deep sea diver’s depth is currently 30 m below the surface of the water.
which expressions represent a change in depth of d meters?
choose exactly two answers that are correct.
a. b.
c. d.