Parallelogram

Parallelogram

Secondary 1

In the figure, \(ABCD\) is a parallelogram. Given that \(\angle DAB=64{}^\circ \), \(\angle CMB=70{}^\circ \) and \(\angle BCM=36{}^\circ \). Find

  1. \(\angle BCD\),
  2. \(\angle CBM\),
  3. \(\angle BDC\),

stating your reasons clearly.

Source consistency note: The exact angle labels are inconsistent with a parallelogram. The angle chase gives \(\angle BAM=28^\circ,\angle ABM=42^\circ,\angle CBM=74^\circ\). The sine rule gives \(AM/BM=\sin42^\circ/\sin28^\circ\), but \(CM/BM=\sin74^\circ/\sin36^\circ\); these are unequal, contradicting \(AM=CM\). The numerical answers below are conditional angle-chasing results, not angles of a figure satisfying every label.

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Answer:(a) \(64^\circ\); (b) \(74^\circ\); (c) \(42^\circ\). The results are conditional; the exact source labels conflict.

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