Question

if x=3 is one root of polynomial x2-2kx-6. find k

Answer 1

(3)^2-2×3k-6=0
9-6k-6=0
-6k=-3
K=3/6
K=1/2....…is the value of k

Answer 2

Since x=3,
P(x)=x^2-2kx-6,
Substitute value of x in p(x).
Therefore,
p(3)=(3)^2-2k(3)-6
p(3)=0
0=9-6k-6
0=3-6k
k=3/6
k=1/2


I hope this helps...!✌