Question

If both the zeroes of a quadratic polynomial ax²+bx+c are equal and opposite in sign, find b.

Answer 1

Let $p$ and $-p$ are two zeroes of the quadratic polynomial which are equal and opposite sign.

We know that-

Sum of the zeroes $=\frac{-b}{a}$
So,

$p+(-p)=\frac{-b}{a}$
$0=\frac{-b}{a}$
Therefore,
$b=0$

Hence, value of $b$ is $0$