Răspuns :
2(L+l)= 878
3(l-15)= L
2[ 3(l-15) + l] = 878 | :2
3(l-15) + l = 439
3l - 45 + l = 439
4l = 439+ 45
4l = 484
l= 121
3(121-15)= L
3 *106= L
318= L
Perimetru romb = 318 *2= 636
4*a= 636
a= 159
3(l-15)= L
2[ 3(l-15) + l] = 878 | :2
3(l-15) + l = 439
3l - 45 + l = 439
4l = 439+ 45
4l = 484
l= 121
3(121-15)= L
3 *106= L
318= L
Perimetru romb = 318 *2= 636
4*a= 636
a= 159