81 = s⊃2;

s⊃2; = 81

s = √81

s = 9 cm

Volume limas = 1/3 x luas alas x tinggi

162 = 1/3 x 81 x t

162 = 27 x t

t = 162 / 27

t = 6

Tinggi segitiga sisi tegak = Ts

Ts = √(t⊃2; + (1/2 s)⊃2;

Ts = √(6⊃2;+4,5⊃2;)

Ts = √56,25 = 7,5 cm

Luas seluruh sisi tegak limas = 4  x luas bidang tegak

= 4 (1/2 x s x Ts)