yang tau Luasnya dunks......

L = L¹ * 2 + K * T
L¹ = ( a + b ) / 2 * t
t = y
y = 9 - 6 = 3
y = 5² - 3² = √16 = 4 ( t )
L¹ = ( 9 + 6 ) / 2 * 4 = 30 cm * 2 = 60 cm²
L² = K * t
K = 9 + 6 + 4 + 5 = 24
L² = 24 * 20 = 480 cm²
total = 480 + 60 = 540 cm²
Luas = 540 cm²

cari tinggi alas dulu :
pakai tripel phytagoras biar cepat. (3,4,5)
alas segitiga= 9-6 = 3 cm
sisi miring =5 cm
maka tingginya prisma= 4 cm

Lp = 2La + kell alas.t prisma
= 2. (a+b)t/2 + a+b+c+t x t prisma
=2. 15.4/2 + (6+9+5+4) x 20
=60 + 480
=540 cm2