Jawabanmu

2014-05-29T08:10:00+07:00
Diagonal alas = 20
akar r^2+r^2 = 20
r^2 + r^2 = 20^2
2r^2 = 400
r^2 = 200
r = akar 200
r = 10 akar 2

luas alas = r x r = 10 akar 2 x 10 akar 2 = 100 akar 4 = 100 x 2 = 200

panjang rusuk tegak = 26
akar 10^2 + t limas ^2 = 26
10^2 + t^2 = 26^2
100 + t^2 = 676
t^2 = 576
t = 24

volume = 1/3 x luas alas x t
           = 1/3 x 200 x 24
           = 1600