The triangle is an isosceles triangle. This is because it has 2 equal sides.
Side AB : 8 - 3 = 5 based on the y-axis
Side AC : 7 - 2 = 5 based on the x-axis
Side BC : 8 - 5 = 3 based on the y-axis
Area of an isosceles triangle = (base * height) / 2
The height is the line that runs in the middle of the triangle. It is the long leg of a right triangle. We need to solve for the height before we can solve for the area of the isosceles triangle.
Side BC is the short leg. It must be divided by 2. 3/2 = 1.5
Side AB or AC will serve as the hypotenuse.
Pythagorean theorem: a² + b² = c²
a² + 1.5² = 5²
a² + 2.25 = 25
a² = 25 - 2.25
a² = 22.75
a = √22.75
a = 4.77 This is the height.
Area = (3 * 4.77)/2 = 14.31/2 = 7.155 square unit