Consider a right triangle where one of the angles is measured at $30^{ ext{o}}$. If the length of the side opposite to this angle is 4 units, what is the length of the hypotenuse of the triangle?
Recall the sine function: for an angle $\theta$ in a right triangle, the sine is defined as the ratio of the length of the opposite side to the hypotenuse:
$$ \sin(\theta) = \frac{\text{opposite}}{\text{hypotenuse}} $$