where a is a constant, we can find a with the first statement:
"an object falls 64 feet in 2 seconds"
so:
[tex]\begin{gathered} 64=a(2)^2 \\ a=\frac{64}{2^2} \\ a=16 \end{gathered}[/tex]the complete equation is
[tex]d(t)=16t^2[/tex]now "determine the distance for 6seconds"
so, replace t=6 and find d
[tex]\begin{gathered} d(t)=16(6)^2 \\ d(t)=576ft \end{gathered}[/tex]the distance is 576ft