Answer:
40ft
Step-by-step explanation:
The volume of a square pyramid is given by:
[tex]V=\frac{l^2h}{3}[/tex]
where V is the volume, l is the length of the square base, and h is the height.
Since we need to find the length, we solve for [tex]l[/tex] in the last equation:
[tex]l^2h=3V\\\\l^2=\frac{3V}{h} \\\\l=\sqrt{\frac{3V}{h} }[/tex]
and now, we substitute the known values:
[tex]V=19,200ft^3\\h=36ft[/tex]
and we get the following:
[tex]l=\sqrt{\frac{3(19,200ft^3)}{36ft} }\\ \\l=40ft[/tex]
the length of the square base is 40ft