Question

Find the value of k for the quadratic equation kx (x-2) + 6=0 so that it has two equal roots.

Answer 1

Solution:

kx(x-2) +6=0

=>kx^2-2kx+6=0

Any quadratic equation is of the form ax^2+bx+c=0

Here,

a = k,b= -2k and c = 6

Given that the above quadratic equation has equal roots, implying that the discriminant is zero.

D=0

=>b^2-4ac=0

=>(-2k)^2-4(k)(6)=0

=>4k^2-24k=0

=>4k(k-6)=0

=>k-6=0

=>k=6

For k=6,the given quadratic equation has equal roots.