Question

Which of these could be the graph of F(x)= 6 • (0.4)^x​

Answer 1

B

Explanation:

to figure out which graph is the graph of the given function. we need to figure out the y-intercept:

to do so

recall exponential function

`y = \displaystyle \: a {b}^(x)`

substitute 0 for x:

`\displaystyle \: y=6 \cdot \: {0.4}^(0)`

recall law of exponent:

`y = \displaystyle \: 6 \cdot \: 1`

simplify multiplication:

`y = \displaystyle \:6`

now two graphs have (0,6) as y-intercept

but remember if b<0 then the function is decreasing

hence,

our answer is B