How to find the length of the side of other quadrilaterals

Practice Questions

ISEE Upper Level Mathematics Achievement › How to find the length of the side of other quadrilaterals

Questions

The perimeter of a quadrilateral is 86. The four sides measure

$15,25,30,\textup{ and }\left ( 2x^{2}\cdot \frac{2}{x}\right )$ .

What is the value of ?