Question

X^2+kx+12,(x+3),then find k

Answer 1

Answer:

k = 7

Step-by-step explanation:

p(x) = x²+kx+12

x+3 = 0

   x = -3

p(-3) => (-3)² + k(-3) + 12 = 0

                         9-3k+12 = 0

                             21-3k = 0

                                -3k = -21

                                 3k = 21

                                  k = 21/3

                           ∴      k = 7

Hope this helpz :)

Answer 2

Answer

as X+3=0 ( given)

X= -3

therefore -3*-3+k*-3+12=0

9+(-3k)+12=0

21-3k=0

therefore 21=3k

k= 21/3

k=7

Hence proved