Question

Find the value of K for which the quadratic equation kx² -2√5 x +4=0 has equal roots​

Answer 1

Answer:

$k = \frac{4}{5}$

Step-by-step explanation:

For equal roots ,

Discriminants should be equal to 0

Here in our quadartic equation

$a = k$

$b = - 2 \sqrt{5}$

$c = 4$

We know that ,

$discriminant = {b}^{2} - 4ac$

${b}^{2} - 4ac = {( - 2 \sqrt{5} )}^{2} - 4(k)(4)$

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

$(4 \times 5) - 16k = 0$

$20 - 16k = 0$

$16k = 20$

$4k = 5$

$k = \frac{4}{5}$