Question

Find area of equilateral triangle ABC, where A : (1, –3) and BC
2x-y+3=0​

Answer 1

Answer:

perpendicular distance of A from BC =

{(2×1) + (-1)×(-3) + 3}/√((2^2)+(1^2))

= ((2+3+3)/(√(4+1))

=8/√5 = (√3/2)×a where is the side of equilateral triangle. This gives

a = 16/√15

Area of equilateral triangle = (√3/4)×a^2

put this value of a in this formula

A = (√3/4)×16×16/15

=64√3/15 Ans