Panjang AD =20 cm, AE =12 cm, dan EB =28 cm. Jika luas permukaan prisma 4.280 cm², tinggi prisma tersebut.... cm

DE² = 20² - 12²
= 400 - 144
= 256
DE = √256
= 16 cm
AB = AE + EB
= 12 + 28
= 40 cm

L prisma = (2×AB×DE) + (keliling ×
t.prisma)
4280 = (2 × 40 × 16) + [(40+40+20+20) × t]
= 1280 + 120t
120t = 4280 - 1280
t = 3000/120
t = 25 cm
jadi tinggi prisma = 25 cm