If the zeroes of the rational expression (3x + 2a) (2x + 1) are -1/2

1.	If the zeroes of the rational expression (3x + 2a) (2x + 1) are -1/2 and b/c then the value of a is ………………A) -b/3B) -b/2C) -2b/3D) 2b/3
Answer» Correct option is (B) -b/2 \(\frac{b}{3}\) is a zero of expression (3x+2a) (2x+1) \(\therefore(3\times\frac b3+2a)(\frac{2b}3+1)=0\) \(\Rightarrow\) (b+2a) \(=\frac0{\frac{2b}3+1}=0\) \(\Rightarrow\) 2a = -b \(\Rightarrow\) a = \(\frac{-b}2\) Correct option is B) -b/2

If the zeroes of the rational expression (3x + 2a) (2x + 1) are -1/2 and b/c then the value of a is ………………A) -b/3B) -b/2C) -2b/3D) 2b/3

Answer»

Correct option is (B) -b/2

\(\frac{b}{3}\) is a zero of expression (3x+2a) (2x+1)

\(\therefore(3\times\frac b3+2a)(\frac{2b}3+1)=0\)

\(\Rightarrow\) (b+2a) \(=\frac0{\frac{2b}3+1}=0\)

\(\Rightarrow\) 2a = -b

\(\Rightarrow\) a = \(\frac{-b}2\)

Correct option is B) -b/2