Answer:
16
Step-by-step explanation:
The area of a parallelogram is b * h, where b and h are the base and height respectively. We know the base but not the height. However, we see a right triangle that has the height and 3 as legs and 5 as the hypotenuse. Pythagorean Triples tell us that the height is 4 and the area will be 4 * 4 = 16 sq. units. Hope this helps!