Given data:
ABC is a triangle such that,
[tex]\begin{gathered} \angle B=90^{\circ} \\ AB=5\operatorname{cm} \\ BC=12\operatorname{cm} \end{gathered}[/tex]
The triangle will look like this,
The given traingle is a right angle tringle since one of the angle is 90 degree.
to find the length of the side AC we use the phythagoras theorem, that is,
[tex]AC^2=AB^2+BC^2[/tex]
now subsitute the values of sides respectively,
[tex]\begin{gathered} AC^2=5^2+12^2 \\ AC=\sqrt[]{25+144} \\ AC=\sqrt[]{169} \\ AC=13 \end{gathered}[/tex]
Thus, the length of AC = 13.
