Question

The axis of symmetry for the graph of the function f(x)=3x^2+bx+4 is x= 3/2. what is the value of b

Answer 1

Answer:

b = -9

Step-by-step explanation:

The function is given as :

$f(x)=3x^2+bx+4$

The axis of symmetry for this function is x = 3/2

It is required to find the value of b. The axis of symmetry of a parabola is a vertical line that intercepts its vertex at its horizontal coordinate. It can be given by :

$x=\dfrac{-b}{2a}$

Putting x = 3/2 and a = 3 we get :

$b=-2ax\\\\b=-2\times 3\times \dfrac{3}{2}\\\\b=-9$

So, the value of b is -9.