Подробное объяснение:
b = 1/3 * a
h = 1/3 * b
V = a * b *h = 216
a * 1/3 * a * 1/3 * b = 216
a * 1/3 * a * 1/3 * 1/3 * a = 216
a = 18 см
b = 1/3 * 18 = 6 см
h = 1/3 * 6 = 2 см
![\frac{a^{3} }{27} =216\\\\a^{3} = 216 * 27 \\\\a^{3} = 5832\\\\a = \sqrt[3]{5832}\\\\a = 18 cm](/tpl/images/1861/0289/0466e.png)
