Question

Find the value(s) of $k$ for which the equations $x^2+5kx+16=0$ has real and equal roots.

Answer 1

To find: the value of $k$

Equation : $x^2+5kx+16=0$

Eqn has real and equal roots

So, $b^2-4ac=0$

$25k^2-4\left(16\right)\left(1\right)=0$

$k^2=\frac{64}{25}$

$k=\pm \frac{8}{5}$