Step 1:

The points are , and .

Graph the points  , and  .

Step 2:

The distance between and is .

The distance between and

The distance between and

The distance between and

Pythagoras theorem,

In a right angle triangle ABC,

Hence the triangle ABC is right angle triangle.

Step 3:

The area of a right angle triangle is .

Where and .

Solution:

ABC is right angle triangle.

Area of triangle ABC is 6.5