1. **Problem 14:** Find the value of angle $b$ given the intersecting lines and angles 43°, 68°, and 69°. 2. When two lines intersect, opposite (vertical) angles are equal. 3. The angles around a point sum to 360°. 4. From the image, angle $b$ is vertically opposite to the angle adjacent to 68° and 69°. 5. Calculate the angle adjacent to 68° and 69°: $$\text{Adjacent angle} = 360^\circ - (68^\circ + 69^\circ + 43^\circ)$$ 6. Simplify: $$= 360^\circ - 180^\circ = 180^\circ$$ 7. Since $b$ is vertically opposite to this adjacent angle, $b = 180^\circ$. **Final answer:** $$b = 180^\circ$$