Answer: - Let E1 be electric field due to charge 16nc. Let E2 be electric field due to charge 8nc.
E = 1 / 4 П Е (q1 / r²)
The resultant electric field is given by = √ (E1² + E2² + 2.E1.E2.cos Ф
Here E1 - 16 x 10⁴, E2 - 8 x 10⁴, since it is equilateral triangle Ф = 60°
Substituting the values we get,
E = 21.2 x 10⁴
Direction of resultant electric field will be along and away from perpendicular bisector of BC.