Algebra and Trigonometry 10th Edition

Part A: $\frac{\pi}{4}$,$\frac{7\pi}{4}$ Part B: $\frac{3\pi}{4}$,$\frac{5\pi}{4}$
Using the unit circle, two angles that work are: Part A: $\frac{\pi}{4}$,$\frac{7\pi}{4}$ Part B: $\frac{3\pi}{4}$,$\frac{5\pi}{4}$