Question

if the roots of the quadratic equation x square plus 12 x plus a is equal to zero are real and equal then find the value of a
please reply with explanation​

Answer 1

Answer:

⇒ Given quadratic equation is kx

2

−2

5

x+4=0, comparing it with ax

2

+bx+c=0.

⇒ We get, a=k,b=−2

5

and c=4

⇒ It is given that roots are real and equal.

∴ b

2

−4ac=0

⇒ (−2

5

)

2

−4(k)(4)=0

⇒ 20−16k=0

⇒ 16k=20

⇒ k=

16

20

⇒ k=

4

5

∴ Given value of k is correct