Question

The zeroes of the quadratic polynomial \(2x^2 -3x - 9\) are:

(A) \(3, \frac{-3}2\)

(B) \(-3, \frac{-3}2\)

(C) \(-3, \frac{3}2\)

(D) \(3, \frac{3}2\)

Answer 1

Correct option is (A) \(3, \frac{-3}2\) 

Let the polynomial \(P(x)=2 x^2-3 x-9\).

\(P(x) =2 x^2-3 x-9\)

\(=2 x^2-6 x+3 x-9 \)

\(=2 x(x-3)+3(x-3)\)

\(=(x-3)(2 x+3)\)

The value of polynomial \(P(x) = 0\).

\(\Rightarrow (x-3)(2 x+3)=0\)

\(\Rightarrow(x-3)=0 \text { or } (2 x+3)=0\)

\(\Rightarrow x=3 \text { or } x=\frac{-3}{2}\)

Therefore, the zeroes of polynomial are 3 and \(\frac{-3}{2}\).

Answer 2

The zeroes of the quadratic polynomial 2x ² − 3x − 9 are: (A)  3 , − 3/2