Sebuah limas alas berbentuk persegi mempunyai luas luas alas 81cm dsn volume 162. Hitunglaj sisi tegak!
feliciawijayaa
Sisi = 9 cm V = 1/3 x La x t 162 x 3 = 81 x t 486/81 = t 6 = t sisi tgk = √36 + 20,25 = √56,25 =7,5 cm
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Brillianttt
tinggi limas = 3 x Volume / luas alas = 3 x 162 / 81 = 3 x 2 = 6 cm sisi alas = √ Luas = √81 = 9 cm diagonal als = sisi√2 = 9√2 cm sisi tegak = √(1/2 d)² + t² = √(9/2√2)² + 6² = √81/2 + 36 = √ 81/2 + 72/2 = √153 / √2 cm = √9 x 17 / √2 cm = 3/2 √34 cm
V = 1/3 x La x t
162 x 3 = 81 x t
486/81 = t
6 = t
sisi tgk = √36 + 20,25 = √56,25
=7,5 cm
sisi alas = √ Luas = √81 = 9 cm
diagonal als = sisi√2 = 9√2 cm
sisi tegak = √(1/2 d)² + t²
= √(9/2√2)² + 6²
= √81/2 + 36
= √ 81/2 + 72/2
= √153 / √2 cm
= √9 x 17 / √2 cm
= 3/2 √34 cm