\(\Sigma Fx=0\)
\(\Sigma Fy=0\)
\(Tx-Tx=0\)
\(Ty+Ty-W=0\)
\(2Ty=W\)
\(Ty=\ \frac{w}{2}\)
\(T\ Sin\theta=\frac{w}{2}\)
\(T=\frac{w}{2}Sin\ \theta=\frac{m\left(g\right)}{2\ Sin\theta}=\frac{\left(10kg\right)\left(9.81\right)}{2\ Sin\theta}=\frac{98.1}{1.73}=56.70N\)