Question

Ab" that goes through points (0,9)

Answer 1

$y = ab^x \\\\[-0.35em] ~\dotfill\\\\ (\stackrel{x}{0}~~,~~\stackrel{y}{9})\qquad \implies 9=ab^0\implies 9=a(1)\implies 9=a~\hfill \underline{y=9b^x} \\\\\\ (\stackrel{x}{10}~~,~~\stackrel{y}{9216})\qquad \implies 9216 = 9b^{10}\implies \cfrac{9216}{9}=b^{10}\implies 1024=b^{10} \\\\\\ \sqrt[10]{1024}=b\implies 2=b~\hfill \underline{y=9(2)^x}$