In the diagram above, quadrilateral ABCD is a rhombus. If the m∠DAB

= 124°
find the measurements below. Which answer is correct and why

(3 points)
m∠ABC=

°

m∠AEB=

°

m∠ADE=

°

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1 answer

To solve the problem, we need to use the properties of a rhombus and its angles.

  1. Properties of a Rhombus:
    • All sides are equal in length.
    • Opposite angles are equal.
    • Adjacent angles are supplementary (add up to 180°).

Given that \( m∠DAB = 124° \):

  1. Finding \( m∠ABC \):

    • Since \( ABCD \) is a rhombus, \( m∠DAB \) and \( m∠ABC \) are opposite angles.
    • Therefore, \( m∠ABC = m∠DAB = 124° \).
  2. Finding \( m∠ADE \):

    • To find the adjacent angle \( m∠ABC \), we use the property that adjacent angles are supplementary.
    • \( m∠DAB + m∠ABC = 180° \)
    • Thus, \( m∠ABC = 180° - m∠DAB = 180° - 124° = 56° \).
    • Therefore, \( m∠ADE = m∠ABC = 56° \).
  3. Finding \( m∠AEB \):

    • Point E is the intersection of the diagonals of the rhombus. In a rhombus, the diagonals bisect the angles.
    • Since \( m∠DAB = 124° \), \( m∠EAB = \frac{1}{2} m∠DAB = \frac{1}{2} (124°) = 62° \).
    • Similarly, \( m∠ABE = \frac{1}{2} m∠ABC = \frac{1}{2} (56°) = 28° \).
    • In triangle \( AEB \), we have: \[ m∠AEB = 180° - (m∠EAB + m∠ABE) = 180° - (62° + 28°) = 180° - 90° = 90°. \]

Final Measurements:

  • \( m∠ABC = 56° \)
  • \( m∠AEB = 90° \)
  • \( m∠ADE = 124° \)

Summary of Answers

  1. \( m∠ABC = 56° \)
  2. \( m∠AEB = 90° \)
  3. \( m∠ADE = 124° \)

These calculations utilize the properties of a rhombus, specifically the relationships between its angles and the bisection by diagonals.