Question
Question: The value of 'a' for which the equations x<sup>2</sup> – 3x + a = 0 and x<sup>2</sup> + ax – 3 = 0 ...
The value of 'a' for which the equations x2 – 3x + a = 0 and
x2 + ax – 3 = 0 have a common root is -
A
3
B
1
C
–2
D
2
Answer
2
Explanation
Solution
x2 – 3x + a = 0 & x2 + ax – 3 = 0
Ž (a + 3) (9 – a2) = (a + 3)2 (common root)
(a + 3) [9 – a2 – (a + 3)] = 0
a = – 3 or a2 + a – 6 = 0
a = – 3 or a = – 3 or 2 Ž a = 2