tlg jawabin pk cara bsk dikumpulin

misal
panjang = x = 2y + 5
lebar = y

K = 2 × ( p + l )
82 = 2 × ( x + y )
82 ÷ 2 = ( 2y + 5 + y )
41 = 3y + 5
3y = 41 - 5
y = 36 ÷ 3
y = 12
jadi
p = x = 2y + 5 = 2(12) + 5 = 24 + 5 = 29 cm
l = y = 12 cm

L = p × l
= 29 × 12
= 348 cm²