1. **Problem Statement:** We need to find the measure of angle 3 in the given rectangle with diagonals intersecting and angles marked.
2. **Understanding the figure:** The rectangle has diagonals intersecting, creating four segments labeled 3, 4, 2, and 1. One angle near the diagonal intersection is 116°, and the rectangle has right angles (90°) at its corners.
3. **Key properties:**
- Diagonals of a rectangle are equal in length and bisect each other.
- The sum of angles around a point is 360°.
- Adjacent angles on a straight line sum to 180°.
4. **Using the given angle:** The angle near the diagonal intersection is 116°. The adjacent angle on the same straight line is:
$$180^\circ - 116^\circ = 64^\circ$$
5. **Finding angle 3:** Since the diagonals bisect each other, the angles formed at the intersection are vertical angles and equal. Angle 3 is vertical to the 64° angle, so:
$$\text{angle 3} = 64^\circ$$
6. **Final answer:**
$$\boxed{64^\circ}$$
Angle 3 7Fac13
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.