He had a loss of $800 at first on his investment and later had consecutive gains of $960 and $230.
Let
His investment = y
The balance on his current account will therefore be represented as follows
The integers that represents the loss of $800 = - 800 (the opposite of the gain of 800)
The integers that represents the gain of $960 = 960 (the opposite of a loss of 960)
The integers that represents the gain of $230 = 230 (the opposite of a loss of 230)