Triangle is a part of Rectangle, it is exactly half portion in a rectangle, here I have split an Isosceles triangle into 2 pieces and formed a rectangle figure, using that I derived the area of triangle.
In case if you can’t form a rectangle by splitting the triangle then use the below, fit the triangle in largest rectangle and divide the region as 2 rectangles and then calculate the area of 2 rectangles which will give you the Area of Triangle.
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