Răspuns:
L=3l+5
P=2L+2l=154 =>L+l=77
3l+5+l=77
4l=72 =>l=18 dm
L=18•3+5 =>L=59 dm
A=L•l=59•18 =>A=1062 dm^2
L= 5+ 3l
P= 2(L+l)
154= 2(5+3l+l)
154= 2(5+4l)
154= 10+8l
8l= 154-10
8l= 144
l= 144/8= 18 dm (lățimea)
L= 5+3•18= 5+54= 59 dm (lungimea)
A= 59•18= 1062 dm²