Question

If f(-2) = 10, then f(x)= 3x + ____?

Answer 1

I'm going to use k in place of the blank spot


f(x)= 3x + k

f(-2)= 3(-2) + k ... plug in x = -2 (ie replace every copy of x with -2)

10= 3(-2) + k ... plug in f(-2) = 10 (ie replace every copy of f(-2) with 10)


Now we solve for k

10= 3(-2) + k

10= -6 + k

10+6 = k

16 = k

k = 16


which means that f(x)= 3x + k turns into f(x)= 3x + 16

Answer 2

thank you, you really made me understand.

Answer 3

You're welcome. I'm glad to be of help.

Answer 4

one question, what did you add to get 10 ?

Answer 5

the 10 is given in the portion where it says "f(-2) = 10"

Answer 6

when going from

f(-2)= 3(-2) + k

to

10 = 3(-2) + k

I replaced f(-2) with 10 because it is given that f(-2) = 10

Answer 7

ohhhhh !! okay i got it. lol thank you again

Answer 8

sure thing