275
l=L-13
P=2L+2l=2L+2(L-13)=4L -26=114=> 4L=140=>
L=140/4=35
=>l=35-13=22
=> aria = L*l=35*22=770cmp
276
Cu Pitagora se afla lungimea=90^2-54^2
=8100-2916= 5184
=> lungimea=rad(5184)=72
Aria=L*l= 54*72=3888 cmp.
