Question

Prisma segi 3 abc.def
ab= 17 cm, bc= 8 cm
ac= 15 cm
volume prisma 720 cm3
luas permukaan prisma?
tolong dibantu y, trima ksh!

Answer 1

Q: L.permukaan
= (17x24) + (8x24) + (15x24) + (2x4x15)
= 408 + 192 + 360 + 120
= 1080

Answer 2

S = (1/2)(17+8+15) = 20
Luas alas = √{20(20-17)(20-8)(20-15)} = √{20(3)(12)(5)} =√3600 = 60 cm²
Volume prisma = Luas alas x tinggi
       720          =      60 x t
t = 720/60 = 12 cm
luas permukaan = 2(60) + 17(12) + 8(12) + 15(12)
                        = 120 + 204 + 96 + 180
                        = 600 cm²