Parallelogram Angle Calculation

• What is a parallelogram?

  A four-sided shape with parallel opposite sides
• What can be concluded about the quadrilateral with AB parallel to CD and AD parallel to BC?

  It is a parallelogram
• What are the properties of parallelograms?

  • Opposite sides are parallel and equal
  • Opposite angles are equal
  • Adjacent angles add up to $180^\circ$
• What does it mean when angles are adjacent in a parallelogram?

  They share a side and add up to $180^\circ$
• How do you identify a parallelogram based on its sides?

  Opposite sides must be parallel and equal
• If one angle in a parallelogram is $68^\circ$ and another is $90^\circ +$$x$, how do you find $x$?


  Set up $90^\circ +$$x +$$68^\circ =$$180^\circ$
• What is the equation derived from the angles in the parallelogram?

  $90^\circ +$$x +$$68^\circ =$$180^\circ$
• What is the value of $x$ if $90^\circ +$$x +$$68^\circ =$$180^\circ$?


  $22^\circ$
• What are key terms related to parallelograms?

  • Parallelogram: Opposite sides parallel and equal
  • Opposite angles: Equal angles across from each other
  • Adjacent angles: Angles that add up to $180^\circ$
• What does it mean when one angle in a parallelogram is marked with a square?

  It indicates a right angle of $90^\circ$
• What is the relationship between opposite angles in a parallelogram?

  They are equal
• How do adjacent angles in a parallelogram relate to each other?

  They add up to $180^\circ$
• What can be inferred if a quadrilateral has one right angle?

  It may be a parallelogram