Question

if -4 is a root of the quadratic equation x2+px-4=0 and the quadratic equation x2+px+k=0 has equal roots find the value of k.

Answer 1

Answer:

3/2 is the answer

Step-by-step explanation:

p(X)=x²+px-4

p(-4)=>(-4)²+(-4)p-4=0

      =>16-4p-4=0

     =>p=3

now,

p(x)=x²+px+k

=>p(x)=x²+3x+k (as p=3)

now,

p(x) has same roots

=>b²-4ac=0

here,

b=3

a=1

c=k

=>3²-4(1)(k)=0

=>k=3/2