Question

The figure formed by four points $1+0i;-1+0i,3+4i$ and $\frac{25}{-3-4i}$ on the argand plane is

• A. parallelogram but not a rectangle
• B. a trapesium which is not equilateral
• C. cyclic quadrilateral
• D. none of these

Answer 1

The correct option is A parallelogram but not a rectangle

$1+0i,-1+0i,3+4i,\frac{25}{-3-4i}$

$\frac{25}{-3-4i}\frac{(-3+4i)}{(-3+4i)}$

$=\frac{25(-3+4i)}{25}=-3+4i$.