Question

Alas sebuah limas belah ketupat dgn keliling 60cm dan panjang diagonalnya 18 cm jika tinggi limas 12 cm berapa volume limas tersebut ?

Answer 1

K = 4 s
60 = 4 s
s= 15

d2 = akr (15^2+15^2)
=akr (225+225)
=akr 450
= 15 akr 2

limas = 1/3 x la x t
= 1/3 x (1/2 x d1 x d2) x t
= 1/3 (1/2 x 18 x 15 aakr 2) x 12
=4 ( 9 x 15 akr 2)
=540 akr 2

Answer 2

K = 4xs
60 = 4 x s
s = 60/4
s=15

d2 = 15² - 9²
     = 225 - 81
     = 144
d2 = 12

volume = 1/3 x L.alas x t
            = 1/3 x ( 1/2 x 18 x 12) 12
            = (108) 4
           = 432 cm³