A rectangle has 2 congruent pairs. Those 2 pairs are ST/RU and SR/UT. If that is the case, then that means UV is 5 and SV is also 5. Now we have triangle SRU with a hypotenuse of 10 and a side of 4. Pythagorean Theorem:
4² + b² = 10²
b² = 84
b = 2√21
Segment SR is then equal to b. Now we move on to the area formula:
