PythagorasanglesA right-angle triangle has 90 degree as one of its angle. The hypotenuse is the longest side of a right-angle triangle. Therefore,
Using pythagora's theorem,
[tex]\begin{gathered} x^2=4^2+8^2 \\ x^2=16+64 \\ x^2=80 \\ x=\sqrt[]{80} \\ x=8.94427191 \\ x\approx8.9\text{ cm} \end{gathered}[/tex]
