If 2 is a root of the equation x2 + ax + 12 = 0 and the quadratic equation x2 + ax + q = 0 has equal roots, then q
The given equation x2 + ax + 12 = 0 has a root = 2
So it will satisfy the equation
4 + 2a + 12 = 0
2a + 16 = 0
a = – 8
Putting value of a in second equation, it becomes
x2 + ax + q = 0
x2 – 8x + q = 0
Roots are equal so d = 0
⇒ b2 – 4ac = 0
⇒ 64 – 4q = 0
⇒ q = 64/4
⇒ q = 16