Jawabanmu

2014-04-16T20:22:44+07:00
2 (p+l) = 140
p - l = 20 
p = 20 + l
2 (20+l+l) = 140
2 (20+2l) =140
40 + 4l = 140
4l = 100
l =25 cm
maka, p = 45 cm
3 5 3
2014-04-16T20:22:48+07:00
K= 140 p= l +20 K= 2(p+l) ➡ 2(l+20+l) ➡ 140 = 2(20+2l) ➡ 70= 20+2l ➡ l=25. P= 20+25=45 sorry kalo salah, semoga bermanfaat