Question

if -4 is a root of the quadratic equation X square + kx - 4 is equal to zero and the quadratic equation X square + PX + K is equal to zero has equal roots then find the value of P and K

Answer 1

Answer:

Step-by-step explanation:

-4 is the root of equation x²+kx-4

Put value of x that is -4

(-4)²+k(-4)-4=0

16-4k-4=0

12-4k=0

12=4k

k=12/4

k=3

Put value of k in second equation

x+px+3

This equation has equal roots

So,

Discriminant (b²-4ac)=0

a=1 , b=p ,c=3

p²-4×3×1=0

p²-12=0

p²=12

p=√12

p=2√3,-2√3

Hence k=3

p=2√3,-2√3