The function $f$ is defined by $f(x) = a^x - b$, where $a$ and $b$ ar…

Question

Prompt

The function

f

is defined by

f (x) = a^{x} - b

, where

a

and

b

are constants. In the

x y

-plane, the graph of

y = f (x)

passes through the points

(c, 11)

and

(2 c, 221)

, where

c

is a constant. Which of the following could be the value of

b