ekamiaww
27) volume prisma = luas alas x tinggi prisma = 1/2 x 8 x 6 x 15 = 360 cm³ volume limas = 1/3 x luas alas x tinggi limas = 1/3 x 1/2 x 12 x 11 x tinggi limas = 22 x tinggi limas selisih volume = 360 - (22 x tinggi limas) 162 = 360 - (22 x tinggi limas) tinggi limas = (360 - 162) / 22 tinggi limas = 9 cm (a)
28) tinggi limas = 1/3 x 18 = 6 cm tinggi prisma = 2/3 x 18 = 12 cm volume bangun = volume prisma + volume limas 1400 = (a x a x 12) + (1/3 x a x a x 6) 1400 = 12a² + 2a² 1400 = 14a² a² = 100 a = 10 cm (a)
29) volume limas = 1/3 luas alas x tinggi limas 1568 = 1/3 x a x a x 24 1568 = 8a² a² = 196 a = 14 cm tinggi sisi tegak = 25 cm (triple Pythagoras: 7, 24, 25) luas limas = luas alas + (4 x luas sisi tegak) = (14 x 14) + (4 x 1/2 x 14 x 25) = 196 + 700 = 896 cm² (b)
= 1/2 x 8 x 6 x 15
= 360 cm³
volume limas = 1/3 x luas alas x tinggi limas
= 1/3 x 1/2 x 12 x 11 x tinggi limas
= 22 x tinggi limas
selisih volume = 360 - (22 x tinggi limas)
162 = 360 - (22 x tinggi limas)
tinggi limas = (360 - 162) / 22
tinggi limas = 9 cm (a)
28) tinggi limas = 1/3 x 18 = 6 cm
tinggi prisma = 2/3 x 18 = 12 cm
volume bangun = volume prisma + volume limas
1400 = (a x a x 12) + (1/3 x a x a x 6)
1400 = 12a² + 2a²
1400 = 14a²
a² = 100
a = 10 cm (a)
29) volume limas = 1/3 luas alas x tinggi limas
1568 = 1/3 x a x a x 24
1568 = 8a²
a² = 196
a = 14 cm
tinggi sisi tegak = 25 cm (triple Pythagoras: 7, 24, 25)
luas limas = luas alas + (4 x luas sisi tegak)
= (14 x 14) + (4 x 1/2 x 14 x 25)
= 196 + 700
= 896 cm² (b)
semoga membantu ya :)