perbandingan panjang dan lebar persegi panjang 5: 7. jika kelilingnya 96m, maka luasnya adalah

misal Pnajang = P....Lebar = L
5P = 7L....P = 7/5L
96 = 2P + 2L....Subtitusi
96 = 2 (7/5L) + 2L
96 = 14/5L + 10/5L
96 = 24/5L
96 x 5 /24 = L
L= 20m
P= 7/5 x 20 = 28m
Luas = P x L = 28 x 20 = 560m²

p : l = 5 : 7 p = 5/7 l K = 2(p + l ) 96 = 2 ( 5/7l + l ) 96 = 2 ( 12/7 l ) 96 = 24/7 l l = 96 × 7 : 24 = 4 × 7 = 28 p = 5/7 l = 5/7 × 28 = 5 × 4 = 20 Luas = p × l = 20 × 28 = 560