Mid-points of the sides AB and AC of a triangle ABC are ( 3 , 5 ) and ( -3 , -3 ) respectively,then the length of the side BC is

Answer 1

let A = (h,k). Then

B=(h+2(3-h),k+2(5-k))=(6-h,10-k)
C=(h+2(-3-h),k+2(-3,k))=(-6-h,-6-k)

BC^2 = 12^2+16^2 = 340
BC=√340