Question

Write the function for the graph.

Answer 1

B)

Explanation:

exponential function given by:

`\displaystyle f(x )= a \cdot{b}^(x)`

where:

• a is the y-intercept
• b can be any number

since the function crosses y-axis at (0,4) point

• 
  `a = 4`

to find a we can consider (1,8) point it tells us when x is 1 then y is 8 thus:

`\displaystyle 8= 4 \cdot{b}^(1)`

`\displaystyle 8= 4 \cdot{b}^{}`

divide both sides by 4:

`\displaystyle \boxed{b = 2}`

altogether substitute:

`\displaystyle f(x)= 4 \cdot{2}^(x)`

hence our answer is B)