Question

find the value of k of the quadratic equation have real roots and equal roots 9x²+3kx+4 =0​

Answer 1

Answer:

it may help u

plz mark as brainliest answer

Answer 2

Answer:

• k = ±4

Step-by-step explanation:

Given:

• The equation 9x² + 3kx + 4 = 0​, have real and equal roots.

To Find:

• Find the value of k.

Now, we know that for equal and real roots, Discriminant (D) = 0

⇒ D = b² - 4ac = 0    .........(1)

Now, we know the standard form of quadratic equation,

=> ax² + bx + c = 0

And given equation is,

⇒ 9x² + 3kx + 4 = 0    

Now, compare given equation by standard form,

⇒ a = 9, b = 3k and c = 4

Now, put the values of a, b, and c in equation (1),

⇒ b² -  4ac = 0

⇒ (3k)² - 4 × 9 × 4 = 0

⇒ 9k² - 144 = 0

⇒ 9k² = 144

⇒ k² = 144/9

⇒ k² = 16

⇒ k = √16

⇒ k = ± 4