Question

If the following quadratic equation has two equal and real roots then find the value of k :
$k{x}^2-2\sqrt{5}x+4=0$

Answer 1

$k{x}^2-2\sqrt{5}x+4=0$

For equal & real roots, $D=0$

$D=(2\sqrt{5}{)}^2-4(4k)=0$

$\Rightarrow k=\frac{4\left(5\right)}{16}=\frac{5}{4}$