[tex]The\ volume\ of\ cylinder:V=\pi r^2H\\------------------------\\r=15\ cm\\V=19,782\ cm^3\\\pi\approx3.14\\H=?\\\\subtitute:\\\\19,782=3.14(15)^2H\\\\3.14\cdot225H=19,782\\\\706.5H=19,782\ \ \ \ |divide\ both\ sides\ by\ 706.5\\\\\boxed{H=28\ (cm)}\leftarrow answer[/tex]
