Final answer:
The reference angle for -30° is 30°, which is the positive acute angle formed by the terminal side of the angle and the horizontal axis. Option a is the correct answer.
Step-by-step explanation:
The reference angle is the acute angle (an angle less than 90°) formed by the terminal side of an angle and the horizontal axis. For negative angles, we move in a clockwise direction from the horizontal axis.
To find the reference angle for -30°, you would rotate clockwise from the positive x-axis to the terminal side of the angle.
Since -30° is already an acute angle, its reference angle is the same magnitude but positive. Therefore, the reference angle for -30° is 30°.
The reference angle for -30° is 30°
A reference angle is the positive acute angle between the terminal side of an angle and the x-axis in standard position. To find the reference angle, we can consider the angle in the second quadrant and subtract it from 180°.
In this case, the angle -30° is in the second quadrant. To find the reference angle, we subtract -30° from 180°:
180° - (-30°) = 180° + 30° = 210°.
Since the reference angle should be positive and acute, we subtract it from 180° to get the reference angle:
180° - 210° = -30°
The reference angle for -30° is 30° (option A).