Question

Write an exponential function whose graph passes through the given points (0, - 2) and (- 1, - 4)

Answer 1

`y = 2(0.5) {}^(x)`

Explanation:

Use the general formula of exponential equation

`y = ab {}^(x)`

Plug 0,2 into the function

`- 2 = ab {}^(0)`

`- 2 = a * 1`

`a = - 2`

`y = - 2b {}^(x)`

`- 4 = - 2b {}^( - 1)`

`2 = b {}^( - 1)`

`{2}^{ ( 1)/( - 1) }`

`2 {}^( - 1) = 0.5`

B=0.5

`y = 2(0.5) {}^(x)`