Question

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

Answer 1

`f(-3)=121\\\\subtitute\ x=-3\ and\ f(x)=121\ to\ the\ f(x)=112-kx\\\\121=112-(-3)k\\112+3k=121\ \ \ |subreact\ 112\ from\ both\ sides\\3k=9\ \ \ \ |divide\ both\ sides\ by\ 3\\\\\boxed{k=3}`