If angle $b$ measures $25°$, in which quadrant does its terminal side lie?

• A. Quadrant $1$
• B. Quadrant $2$
• C. Quadrant $3$
• D. Quadrant $4$

Answer: (A)

Verified step by step guidance

1. Recall that the coordinate plane is divided into four quadrants, each corresponding to a range of angle measures: Quadrant I (0° to 90°), Quadrant II (90° to 180°), Quadrant III (180° to 270°), and Quadrant IV (270° to 360°).
2. Identify the given angle measure, which is \(25^{\circ}\), and note that it is a positive angle measured from the positive x-axis in the counterclockwise direction.
3. Compare the angle \(25^{\circ}\) to the quadrant ranges to determine where it lies: since \(25^{\circ}\) is greater than 0° and less than 90°, it falls within the range of Quadrant I.
4. Conclude that the terminal side of the angle measuring \(25^{\circ}\) lies in Quadrant I based on the angle's measure and the quadrant definitions.
5. Remember that angles between 0° and 90° always lie in Quadrant I, which is the region where both x and y coordinates are positive.