# Equation 3

Expand the following: \begin{align} F_A^2=F_{AX}^2+F_{AY}^2 =&\cssId{Step1}{F_A= √(F_{AX}^2+F_{AY}^2)}\\[3px] \end{align}

1. Firstly, we use Pythagoras to know the diagonal force because It's the resultant.
2. Secondly, we pass the square root to the two terms of the other side.