Respostas

2013-06-24T17:39:17-03:00

S=L.l

48=x. (x+8)
48=x²+8x
x²+8x-48=0

b²-4.a.c

8²-4.1.-48

192+64

V256=16

 

x=-b+-d/2.

x=-8+-16/2

x1=4

x2=-12

 

Então: l=4cm

L=4+8=12cm