Notes
- Capital letters are always used to represent the vertices of the three angles of a triangle.
- Lowercase letters are often used to represent the sides of a triangle.
- θ is the REFERENCE ANGLE in the example (below).
- θ is a Greek letter, often used to represent geometric variables.
θ is the Reference Angle in this Example
x is the reference angle in this example.
Key Terms
- Right Angle – a 90° angle (NOT a reference angle in Trig).
- Right Triangle – a triangle with a 90° angle.
- Reference Angle – a given ACUTE (less than 90°) angle within a right triangle.
- Legs – Smallest two sides of a right triangle.
- They are perpendicular to one another, and adjacent to the 90° angle.
- Opposite Leg – the SIDE across from the reference angle.
- Adjacent Leg – the SIDE next to (and attached to) the reference angle (not the Hypotenuse)
- Hypotenuse – the longest side of a right triangle. It is across from the 90° angle.
