Expand the following: \begin{align} ΣY=0 =&\cssId{Step1}{2F_{TY}*sin(α)-mg=0}\\[3px] &\cssId{Step2}{F_{TY}*sin(α)=+\frac{mg}{2}}\\[3px] &\cssId{Step3}{F_{TY}=\frac{mg}{2*sin(α)}}\\[3px] \end{align}

- Firstly, we pass mg to the other side so It's positive.
- Secondly, we pass the 2 (that multiplies the tension force) to the other side.
- Thirdly, we pass the sin(α) to the other side multiplying the 2.