Question

the value of k for which x+7 is factor of p(x)=-x^2-kx+7 is given as 6. justify

Answer 1

x+7 is a factor of p(x)

x-(-7) is a factor of p(x)

-7 is a zero of p(x) [By factor theorem]

p(x)= -x²-kx+7

p(-7)= -49+7k+7=0

p(-7)= -42=-7k

p(-7)= 6=k

k= 6

Justified