Question

if one zero of the quadratic polynomial x²-5x + k is -4 ,the value of k is ​

Answer 1

p(x) = x²-5x + k

p(-4) = (-4)²-5(-4) + k = 0

=> 16 +20 +k = 0

=> k = -36

Answer 2

Given equation

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

-4 is the zero of the polynomial

Substituting x = -4 in the given equation, we get,

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

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

$\implies 16+20+k=0$

$\implies 36+k=0$

$\implies k=-36$

$\boxed{\boxed{\bold{Therefore, \ the \ value \ of \ k \ is \ -36}}}}}}}}$