Question

37.1f one zero of the quadratic
polynomial x + 3x + b is 2, then the
value of b is
10
9
8
-10​

Answer 1

Answer:

value of b= 8 is correct answer

Answer 2

Correct Question

If one zero of the quadratic polynomial $\tt{x^2 + 3x + b}$ is 2, then the value of $\tt{b}$ is:

Required Answer

The value of $\tt{b}$ is -10.

Solution

If 2 is one of the zeroes of the given polynomial, then we can say that $\tt{x = 2}$. This implies that:

$\tt{\Longrightarrow f(x) = 0}$

$\tt{\Longrightarrow f(2) = 0}$

$\tt{\Longrightarrow (2)^2+3 \times 2+b = 0}$

$\tt{\Longrightarrow 4+6+b = 0}$

$\tt{\Longrightarrow 10+b = 0}$

$\tt{\Longrightarrow b = -10}$