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

= 124 °
find the measurements below.

(3 points)
m∠ABC=

°

m∠AEB=

°

m∠ADE=

1 answer

To find the measurements of the angles in rhombus ABCD, we can use the properties of rhombuses.

  1. In a rhombus, all sides are equal, and opposite angles are equal. The sum of the interior angles of any quadrilateral is 360°.

  2. Given that \( m \angle DAB = 124° \), we know that:

    • \( m \angle ABC = 124° \) (since opposite angles in a rhombus are equal)
  3. To find \( m \angle BCD \) and \( m \angle CDA \):

    • Since \( m \angle DAB + m \angle ABC + m \angle BCD + m \angle CDA = 360° \)
    • We also know \( m \angle BCD = m \angle CDA \) (since they are opposite angles).

    Let \( x = m \angle BCD = m \angle CDA \). Therefore: \[ 124° + 124° + x + x = 360° \] \[ 248° + 2x = 360° \] \[ 2x = 360° - 248° = 112° \] \[ x = 56° \] So, \( m \angle BCD = 56° \) and \( m \angle CDA = 56° \).

  4. To find \( m \angle AEB \), since E is the intersection of the diagonals of rhombus ABCD, and the diagonals bisect each other at right angles, we can know that:

    • Angles \( m \angle AEB = \frac{1}{2} m \angle DAB\) since diagonals bisect the angles.

    Therefore, \[ m \angle AEB = \frac{1}{2} \times 124° = 62° \]

  5. Finally, to find \( m \angle ADE \), we can know that \( m \angle ADE = m \angle CDA \) since they are vertically opposite angles. Thus, \[ m \angle ADE = 56° \]

In summary:

  • \( m \angle ABC = 124° \)
  • \( m \angle AEB = 62° \)
  • \( m \angle ADE = 56° \)