Answer:
y = 20 [tex]4^{x}[/tex]
Step-by-step explanation:
Use the points to find the values of a and b
Using (0, 20 ) , then
20 = a[tex]b^{0}[/tex] [ [tex]b^{0}[/tex] = 1 ] , then
20 = a
y = 20[tex]b^{x}[/tex]
Using (3, 1280 ) , then
1280 = 20 b³ ( divide both sides by 20 )
64 = b³ ( take the cube root of both sides )
[tex]\sqrt[3]{64}[/tex] = b , that is
4 = b
Then exponential function is
y = 20. [tex]4^{x}[/tex]