Question

find the value of k for which 3x2 + 2x + k = 0 has equal roots

Answer 1

On comparing the given equation with standard form, we get
a=3 , b=2, c=k

D = 0 (given, equation have equal roots)
b^2 - 4ac = 0
2^2 - 4 × 3 × k = 0
4 - 12k = 0
12k = 4
Ans. k = 4/12 = 1/3

Answer 2

3$x^{2}$ +2x+k=0
For it to have equal roots D = 0
D=$b^{2}$ - 4ac
a=3
b=2
c=k


D= 2^2 - 4(3) (k) =0
   = 4-12k=0
   = 4=12k
   = k=4/12
   = k=1/3