Rectangle $ABCD$ contains a point $X$ such that $AX = 3$, $BX = 3$, and $CX = 3$. Find $DX$.
AX2 + CX2 = BX2 + DX2
32 + 32 = 32 + DX2
DX2 = 32 + 32 – 32
DX2 = 9 ====>> DX = +3
discard negative value DX = 3
.
+176 
