Question

If quadratic equation $x^2-3ax+a^2=9$ has roots of opposite sign, then the sum of all possible values of a equals

• A. 0
• B. -2
• C. 4
• D. 9

Answer 1

Answer: (A)

$\because$ Roots of quadratic $x^2-3ax+a^2=9$ are opposite sign
$\therefore a^2-9<0\Rightarrow -3<a<3$
$\therefore$ Sum of all possible values of $a=0$.