Question

I can't seem to figure out how to solve the question: Find the value of k greater than zero for x²-5k²x+4k² has equal roots.

Answer 1

discriminant = 0

b^2 - 4ac =0

25 - 16 k.k = 0

k = 5/4

Answer 2

x^2-5k^2x+4k^2 is the equation

a=1 ,b=5k^2 and c=4k^2

Since,for equal roots D=0

D=b^2-4ac=0

=(5k^2)^2-4(1)(4k^2)=0

=25k^4-16k^2=0

=25k^4=16k^2

=k^4/k^2=16/25

=k^2=16/25

=k=√16/25

K=4/5.......Is the value of k

U can ask if any doubt