1. Let's clarify what a reflex angle is. A reflex angle is an angle greater than 180 degrees but less than 360 degrees. 2. If you have an angle and you are told it is reflex, it means the measure of the angle $\theta$ satisfies $180^\circ < \theta < 360^\circ$. 3. For example, if you have an angle of $240^\circ$, this is a reflex angle because it is greater than $180^\circ$ and less than $360^\circ$. 4. If you are given a smaller angle and asked to find its reflex angle, you can use the formula: $$\text{Reflex angle} = 360^\circ - \text{given angle}$$ 5. For instance, if the given angle is $120^\circ$, then the reflex angle is: $$360^\circ - 120^\circ = 240^\circ$$ 6. This means the reflex angle corresponding to $120^\circ$ is $240^\circ$. 7. Remember, reflex angles are always the larger angle formed between two lines or rays, going the longer way around the circle.