tolong bantu sy .........

K = 4 x sisi persegi 
    = 4 x s = 100
     s = 100/4 = 25 cm

Lebar = 25 - 5 = 20 cm

K= 2(p+l)
   = 2 (p+20)= 100
    p+20 = 50
   p = 50-20
      = 30

Luas = p x l
        = 30 x 20
        = 600 cm2

k persegi=4 ×s
100cm = 4
100:4 =25 (s)
lebar = 25cm - 5
= 20cm
panjang = 50 -20
=30cm
luas persegi panjang = s×s
=20cm × 30cm
= 600 cm²