Question

for what value of k, are the roots of the quadratic equations 3x2+3kx+27=0 real snd equal

Answer 1

for roots to be equal and real
D=0
b^2-4ac =0
b^2=4ac
(3k)^2=4*3*27
9k^2=4*3*27
k^2=36
k=+6,-6

Answer 2

$Discriminant = b^2 - 4ac$ 
                            = (3k)² - 4(3 × 27)
                            = 9k²  - 324
=====================

For equal roots, discriminant = 0 
         
9k² - 324 = 0

9k² = 324

k² = 324/9 

k² = 36

k = √36

k = -6   Or  6 




i hope this will help you


-by ABHAY