The aid of a free-body diagram is essential for solving this mechanics problem. The summation of horizontal and vertical forces in the system must be equal to zero since the body is in equilibrium.
Summation of x-forces:
T*cos(40)-T*cos(40) = 0
y forces:
2T*sin(40) - 150 = 0
T = 150/2*sin(40) = 100.66 N
Therefore, the tension in each wire would be 100.66 Newtons.