Question

The axis of symmetry for the graph of the function f(x)=3x2+bx+4 is x equals three-halves. What is the value of b? −18 −9 9 18

Answer 1

yes, the correct answer is B: -9

Explanation:

got it right in edg 2020

hope this is of help:)

Answer 2

Answer: B ( - 9 )

Step-by-step explanation: given the function f(x) = 3x^2 + bx + 4

And the axis of symmetry x = 3/2

The formula to calculate the axis of symmetry is :

X = -b/2a

Where

X = 3/2

a = 3

Substitute X and a into the formula

3/2 = -b/ ( 2×3)

3/2 = -b/6

Cross multiply

-2b = 18

b = - 18/2

b = - 9

Therefore, the value of b is -9