Nonlinear system

[aminbcc]

I want to solve this system with NSolve Function with mathematica or matlab
please help me:

Cos[x] + Cos[y] + Cos[z] + Cos[t] + Cos[k] = 4
Cos[5 x] + Cos[5 y] + Cos[5 z] + Cos[5 t] + Cos[5 k] = 0
Cos[7 x] + Cos[7 y] + Cos[7 z] + Cos[7 t] + Cos[7 k] = 0
Cos[11 x] + Cos[11 y] + Cos[11 z] + Cos[11 t] + Cos[11 k] = 0
Cos[13 x] + Cos[13 y] + Cos[13 z] + Cos[13 t] + Cos[13 k] = 0