The Solution.
The diagonals of a rhombus intersect at right angles.
Hence, the length UI is a side in the right-angled triangle below:
By Pythagorean Theorem, we have
[tex]\begin{gathered} |UI|^2=7^2+6^2 \\ |UI|^2=49+36=85 \\ \text{Taking the square root of both sides, we get} \\ |UI|=\text{ }\sqrt[]{85}=9.22\approx9.2 \end{gathered}[/tex]
Thus, the correct answer is 9.2
