Answer: The area of ABC is 50 square units.
Step-by-step explanation:
Area of Triangle =

Base = BC = 5 units
Height = AB?
Going by the Pythagorean Theory, the distance between 2 points can be found by;
=

Length of AB =

Length of AB = 20 units
Area =

Area =

Area = 50 square units
Full question and details are;
Triangle ABC is a right triangle
The length of BC is 5 units.
The area of ABC is ____ square units.