Question

Write an exponential function y = abx for a graph that includes (–3, 16) and (–1, 4)

Answer 1

x increases by 2 and y is halved twice, so b equals 1/2.
(1/2)^(-1) = 2, so a must equal 2 (so that a*b^x will equal 4)
Ending with:
\[y = 2(\frac{ 1 }{ 2 })^x\]