the base BC of an equilateral triangle ABC lies on y-axis.The co-ordinates of the point C are (0,3).If the origin is the mid-point of the base BC, fin the coordinates of point Aand B and hence find the area of ABC.
given ABC is an equilateral triangle. such that BC lies on y-axis.
and origin O is the mid-point of BC.
OC= 3 unit.
the point B will be at a distance 3 unit from O [since O is the mid-point ]
since B is on the y-axis.
the coordinates of B =(0,3)
BC=2*3=6 unit
clearly A will lie on x-axis
let the coordinates of A be (x,0)
therefore
hence the coordinates of A are
and the coordinates of B are (0,3).
area of the equilateral triangle ABC =