The graph shows the number of game systems sold since 2015. Based on this information, which function best models the number of game systems sold in millions x years since 2015?

Question

y=21.35\left(0.7\right)^{x}
y=30.5\left(21.35\right)^{x}
y=30.5\left(1.3\right)^{x}
y=30.5\left(0.7\right)^{x}

Answer 1

The function that best models the number of game systems sold in millions x years since 2015 is:

y=30.5(0.7)^x