Question

if x - 3 is a factor of x square +kx +9 then find the value of k

Answer 1

x-3 =0
=> x=3
x²+Kx+9=0
put x=3
3²+3k+9=0
k= -6.

Answer 2

p(x) =x^2+kx+9
g(x) =(x-3)

Take, x-3=0
x=3

p(3) =(3)^2 + k(3) + 9
=9+9+3k
=18+3k


As we know (x-3) is a factor of p(x)..
Remainder =0
18+3k =0
3k =(-18)
k =(-18)/3
k =(-6)



Hope it will help u....