Question
Question: If one root of the equation x<sup>2</sup> + px + 12 = 0 is 4 while the equation x<sup>2</sup> + px +...
If one root of the equation x2 + px + 12 = 0 is 4 while the equation x2 + px + q = 0 has equal roots, the value of q =
A
449
B
4
C
3
D
12
Answer
449
Explanation
Solution
4 is root of x2 + px + 12 = 0
\ 16 + 4p + 12 = 0
4p = – 28
p = – 7
x2 + px + q = 0 have equal roots
\ p2 – 4q = 0
49 – 4q = 0
q = 449