Question

Find the value of K if the roots of
quadratic equation 3x² - Kx +48 =0 are
real and equal
and its
answer is 24 or -24 how?​

Answer 1

Answer:

k = 24 (or) -24

Given,

Roots are real and equal for :-

$\sf 3x^{2} - Kx + 48 = 0$

To Find :-

Value of 'K'

Solution :-

As,

Roots are real and equal

$\sf\implies\triangle = 0$

Where,

$\sf\triangle Indicates 'b^{2}- 4ac$

General form of Quadratic equation :-

$\sf ax^{2}+bx+c = 0$

Comparing with given equation :- $\sf 3x^{2} - Kx + 48 = 0$

$\sf\implies$ a = 3

b = -K

c = 48

Substituting in :- $\sf\implies\triangle = 0$

$\sf (-K)^{2}- 4\times 3\times 48$ = 0

$\sf k^{2}- 576 = 0$

$\sf K^{2} = 576$

K = $\sqrt{576}$

k = 24 (or) -24