1. **Problem statement:** We are given a circle with center O and points A, B, C, D, and E on the circumference. We need to find the size of angle $x$ at point A inside the circle, given that angle $148^\circ$ is marked at point D on the circumference.
2. **Key fact:** The angle subtended by an arc at the center of the circle is twice the angle subtended by the same arc at any point on the circumference.
3. Since $\angle D = 148^\circ$ is an inscribed angle, the central angle subtending the same arc is:
$$\text{Central angle} = 2 \times 148^\circ = 296^\circ$$
4. The full circle is $360^\circ$, so the reflex central angle corresponding to the other arc is:
$$360^\circ - 296^\circ = 64^\circ$$
5. Angle $x$ at point A subtends the same arc as the central angle of $64^\circ$, so:
$$x = \frac{64^\circ}{2} = 32^\circ$$
6. **Reason:** Angle $x$ is an inscribed angle subtending the arc corresponding to the $64^\circ$ central angle, so it is half of that central angle.
**Final answer:**
$$x = 32^\circ$$
Circle Angle 6494B7
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