Determine an exponential function of the form y=Cb^x

Question

The graph has the points (0,-2) and (1,-6).

Answer 1

By plugging in the first two points, we get -2 = C(b⁰)=C(1) So, C = -2. (Remember, anything to the zero power is equal to 1)

 

Then we get -6 = -2(b¹)

So -6 = -2b

so b = 3

 

So the equation is  y = -2(3^X)

Answer 2

Plug in the points:

-2=cb^0 so c=-2

-6 =-2b^1 so b=3

so y = -2*3^x