1. **Problem Statement:** In rectangle ABCD, the measure of angle AEB is given as 84°. We need to find the measures of angles BDC and EBC.
2. **Important Properties:**
- ABCD is a rectangle, so all angles are 90°.
- Diagonals of a rectangle are equal and bisect each other.
- Point E is the intersection of diagonals AC and BD, so E is the midpoint of both diagonals.
3. **Analyze the angles:**
- Since E is the midpoint of diagonals, triangles AEB and CED are congruent.
- Angle AEB is given as 84°.
4. **Find m∠BDC:**
- Angle BDC is an angle in triangle BDC.
- Since ABCD is a rectangle, diagonal BD is a straight line through E.
- Angles AEB and CED are vertical angles, so m∠CED = 84°.
- Triangle BDC is right-angled at C (since ABCD is a rectangle).
- Using triangle properties, m∠BDC = 180° - 90° - 84° = 6°.
5. **Find m∠EBC:**
- Consider triangle EBC.
- Since E is midpoint of BD, BE = ED.
- Triangle EBC is isosceles with BE = EC.
- m∠EBC = m∠ECB.
- Sum of angles in triangle EBC is 180°.
- m∠BEC = 84° (given as m∠AEB, vertical angles equal).
- So, m∠EBC + m∠ECB + m∠BEC = 180°
- 2 * m∠EBC + 84° = 180°
- 2 * m\cancel{\angle EBC} = 180° - 84°
- 2 * m\cancel{\angle EBC} = 96°
- m\angle EBC = \frac{96°}{2} = 48°
**Final answers:**
$$m\angle BDC = 6°$$
$$m\angle EBC = 48°$$
Rectangle Angles A1Cb88
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