$b^2-4ac$ in the quadratic equation $a{x}^2+bx+c=0$ is called the .

The quadratic equation $a{x}^2+bx+c=0$ has two _____ roots, if $b^2-4ac<0$. $($real and distinct$/$real and equal$/$non-real$)$

$\frac{1}{x-2}+\frac{1}{x-3}=5; \left(x\ne 2, 3\right)$ is a _____ equation.

Quadratic formula is also called as _____ formula. (Aryabhatta, Bhaskara, Sreedharacharya)

Which of the following is a quadratic equation?

Which of the following is not a quadratic equation?

If $x=3$ is a solution of the equation $3x^2+\left(k-1\right)x+9=0$, then $k$ is equal to