What is the value of k in the function ƒ (x) = 112 - kx if ƒ (-3) = 121?

k =

Ok to solve for k, take the function f (x) = 112 - kx plug in the x value, so that would be f (-3) now we know that f (-3) = 121 so how to solve for k is quite easy. In replace f (-3) with 121 and x with - 3

so 121 = 112 - k (-3)

solve for k

subtract 112 from both sides

so that would give you 9 = - k (-3)

use the distributive property on - k (-3)

so that would be 3k = 9

divide both sides by 3

which gives you the answer k=3

Plug - 3 into the function to get 112+3k=f (-3) = 121.

So now can calculate k: 112+3k=121, 3k=9, k=3.