The function $f$ is defined by $f(x)=a^{x}+b,$ where $a$ and $b$ are …

Question

Prompt

The function

f

is defined by

f (x) = a^{x} + b,

where

a

and

b

are constants and

a > 0

. In the

x y

-plane, the graph of

y = f (x)

has a

y

-intercept at

(0, - 20)

and passes through the point

(2, 43)

. What is the value of

a + b