Jawabanmu

2014-04-25T19:34:20+07:00
K = 2 (p + l)
120 = 2 (4x + 2x)
120 = 2 (6x)
120 = 12x
x = 10
Maka, panjang : 4x = 4(10) = 40 cm
          lebar      : 2x = 2(10) = 20 cm
K = 2 (p + l)
120 = 2 (4x + 2x)
120 = 2 (6x)
120 = 12x
x = 10
Maka, panjang : 4x = 4(10) = 40 cm
lebar : 2x = 2(10) = 20 cm
2014-04-25T19:35:23+07:00
Rumus keliling = 2(p+l)=120 p+l=120/2=60 p= perbandingan panjang/ jumlah perbandingan =4/4+2=4/6 l=2/6 p=(4/6) x 60 =40 l=2/6x60= 20