In any rhombus, the diagonals bisect each other at right angles (90°). That is, each diagonal cuts the other into two equal parts, and the angle where they cross is always 90°.
Then
Now that we know the value of [tex]\begin{gathered} 5x+15=m<\text{PAN} \\ 5x+15=90\~ \\ 5x+15-15=90-15 \\ 5x=90-15 \\ \frac{5x}{5}=\frac{90-15}{5} \\ x\frac{5}{5}=\frac{75}{5} \\ x=15 \end{gathered}[/tex]Then x equals 15
