Question

For the function ƒ, c is a constant and ƒ(3) = 12. What is the value of f(−3) ? ƒ(x) = cx2 + 30 A) −12 B) −2 C) 0 D) 12

Answer 1

The answer is D)12

Explanation:

Answer 2

D. 12

Step-by-step explanation:

We have been given a function
`f(x)=cx^(2)+30`, where c is a constant and f(3)= 12.

To find f(-3) we will find value of c by substituting value of f(3) in our given function.

`12=c* 3^(2)+30`

`12=9c+30`

`12-30=9c`

`9c=-18`

`c=(-18)/(9) =-2`

Upon substituting value of c in our given function we will get our function as
`f(x)=-2x^(2)+30`

Now let us find f(-3) by substituting x=-3 in our function.

`f(-3)=-2(-3)^(2)+30`

`f(-3)=-2(9)+30`

`f(-3)=-18+30`

`f(-3)=12`

Therefore, f(-3) is 12 and option D is the correct choice.