In a triangle ABC, coordinates of A are (1, 2) and the equations of the medians through B and C are respectively, x + y = 5 and x = 4. Then area of \[\Delta \] ABC (in sq. units) is :
Solutions · 1
Official solution
Median through C is x = 4
So the coordinate of C is 4. Let C = (4, y), then the midpoint of A(1, 2) and
C(4, y) is D which lies on the median through B.
\[ \therefore \] D =\left( {{{1 + 4} \over 2},{{2 + y} \over 2}} \right) (
Now, \]{{1 + 4 + 2 + y} \over 2}= 5⇒y = 3.
So, C \equiv \[ (4, 3).
The centroid of the triangle is the intersection of the mesians, Here the medians x = 4 and x + 4 and x + y = 5 intersect at G (4, 1).
The area of triangle \]\Delta ABC = 3×ΔAGC
= 3×{1 \over 2}\[ [1(1 \]-3) + 4(3−2) + 4(2−