Write an exponential function in the form y=ab^xy=ab x that goes through points (0, 20)(0,20) and (2, 720)(2,720).

Respuesta :

Answer:

The exponential function that goes through [tex](x_{1},y_{1}) = (0,20)[/tex] and [tex](x_{2}, y_{2}) = (2,720)[/tex] is [tex]y = 20\cdot 6^{x}[/tex].

Step-by-step explanation:

Let be an exponential function of the form [tex]y = a\cdot b^{x}[/tex] that goes through [tex](x_{1},y_{1}) = (0,20)[/tex] and [tex](x_{2}, y_{2}) = (2,720)[/tex]. Then, we have the following system of equations:

[tex]20 = a\cdot b^{0}[/tex] (1)

[tex]720 = a\cdot b^{2}[/tex] (2)

By dividing (2) by (1), we obtain the value for [tex]b[/tex]:

[tex]\frac{720}{20} = b^{2}[/tex]

[tex]b = \sqrt{\frac{720}{20} }[/tex]

[tex]b = 6[/tex]

And the value for [tex]a[/tex] is found by (1):

[tex]a = 20[/tex]

The exponential function that goes through [tex](x_{1},y_{1}) = (0,20)[/tex] and [tex](x_{2}, y_{2}) = (2,720)[/tex] is [tex]y = 20\cdot 6^{x}[/tex].