can someone help me find the length of the other diagonal ??

Remember that
the area of a rhombus is equal to
[tex]A=\frac{1}{2}\cdot(D1\cdot D2)[/tex]where
D1 and D2 are the diagonals
substitute the given values
[tex]59.5=\frac{1}{2}\cdot(14\cdot D2)[/tex]solve for D2
[tex]\begin{gathered} 119=14\cdot D2 \\ D2=\frac{119}{14} \\ D2=8.5\text{ in} \end{gathered}[/tex]