Answer
Shortest side = 5
Side opposite 60° = 5$\sqrt 3$ $\approx 8.66$
Work Step by Step
Given that
Longest side = 10
We know that, the longest side of a 30°–60°–90° triangle is twice the shortest side and the side opposite the 60° angle is $\sqrt 3$ times the shortest side.
Therefore
Shortest side = $\frac{longest side}{2}$ = $\frac{10}{2}$ = 5
Side opposite 60° = $\sqrt 3\times $ shortest side = $\sqrt 3 \times$5 = 5$\sqrt 3$
Side opposite 60° $\approx 8.66$
