Question

Find the value of k for which the equation xsqure+5kx+16=0 has real root
And equal root

Answer 1

p(x)
$= x {}^{2} + 5kx + 16 = 0$
a
$a = 1 \\ b = 5k \\ c = 16$
$b {}^{2} { - 4a}c = 0$
$5k {}^{2} = 4 \times 1 \times 16$
$25k {}^{2} = 64$

ksquare =64by 25

$k = 64 \frac{1}{25}$
k =√64 \25

k=8by 5