Answer:
16 units²
Step-by-step explanation:
Diagonal AC is a vertical line extending from y=0 to y=4, so is 4 units long.
Diagonal BD is a horizontal line extending from x=-5 to x=3, so is 8 units long.
The area of a rhombus is half the product of the lengths of the diagonals, so ...
A = (1/2)(4 units)(8 units) = 16 units²
The area of rhombus ABCD is 16 units².