Given data:
The first given length is AC=53.
The second given length is AB= 45.
The expression for the Pythagoras theorem is,
[tex]\begin{gathered} AB^2+BC^2=AC^2 \\ (45)^2+BC^2=(53)^2 \\ BC^2=784 \\ BC=28 \end{gathered}[/tex]
Here, consider only positive sign of BC length as side cannot negative.
Thus, the BC length is 28.
