In a right triangle, if $a$ and $c$ are the lengths of the leg and hypotenuse respectively, which of the following expressions represents $sin\theta$ where $\theta$ is the angle opposite side $a$?

In a right triangle, if two triangles have their corresponding acute angles equal, which angles are congruent to each other?

If an angle in a right triangle measures $x$ degrees, what is the measure of its supplement?

Which equation correctly relates the measure of angle ${\theta }_1$ in a right triangle to the lengths of the opposite side $O$ and the hypotenuse $H$?

Which of the following sets of measurements could represent the side lengths in feet of a right triangle?

Given that $\cos \left(\theta \right)$ = $\frac{3}{10}$, what is the value of $\sin \left(\theta \right)$ if $\theta$ is an acute angle?

Given a right triangle where the side opposite angle $\theta$ has length $3$, the adjacent side has length $4$, and the hypotenuse has length $5$, what is the equation for the trigonometric function $f\left(x\right)$ that represents $sin$ of angle $\theta$ in terms of these side lengths?

Given that $\sin \left(\theta \right)$ = $-\frac{12}{13}$, and that $\theta$ is in the third quadrant, what is the value of $\cos \left(\theta \right)$?

In the context of right triangle trigonometry, which trigonometric function is represented by the equation $x=a\sin wt$?