Derivation of area of triangle formula please
Dear Student!
Here is the answer to your query.
Let ABC be a triangle whose vertices are A (x1, y1), B (x2, y2) and C (x3, y3)
Now AL, BM and CN perpendicular from A, B, C on x - axis.
Clearly ABML, ALNC and BMNC are all trapeziums
we know that
Area of trapezium = (Sum of parallel sides) (Distance between them)
Now Area of Δ ABC = Area (ABML) + Area (ALNC) – Area (BMNC)
= (BM + AL) (ML) + (AL + CN) (LN) – (BM + CN) (MN)
Cheers!