Right, Acute & Obtuse Angles

Right, Acute & Obtuse Angles exercise

• Identify the types of angles.

  Hints

  A right angle is the most common angle and forms a perfect square at the corner of the arc.

  A complete circle is 360°.

  An acute angle is less than 90°.

  An obtuse angle is more than 90° and less than 180°.

  Solution

  • A straight angle or line is 180°.
  • A reflex angle is more than 180° but less than 360°.
  • A right angle is 90°.
  • A complete angle is 360°, or a full circle.

• Define the terms.

  Hints

  Most angles have arcs.

  Remember, an angle less than a right angle is an acute angle.

  A vertex is where two or more lines meet.

  Solution

  • Obtuse angles have a large arc, more than 90° and less than 180°.
  • Acute angles have a small arc less than 90°.
  • The vertex is the point where two rays meet to form an angle.
  • Right angles measure exactly 90°.

• Sort different angles.

  Hints

  An acute angle is less than 90°.

  An obtuse angle is more than 90° and less than 180°.

  Two choicies are acute angles, two choices are obtuse angles and one choice is a right angle.

  Solution

  OBTUSE ANGLES are more than 90° and less than 180°

  • 120°
  • 150°

  ACUTE ANGLES are less than 90°

  • 60°
  • 45°

  A RIGHT ANGLE is 90°

• Identify the types of angles.

  Hints

  A complete circle is 360°.

  An acute angle is less than 90°.

  A reflex angle is more than 180° but less than 360°.

  A straight angle is also known as a line.

  Solution

  REFLEX ANGLES are more than 180° and less than 360°

  • 215°
  • 197°

  ACUTE ANGLES are less than 90°

  • 45°

  A STRAIGHT ANGLE is 180°
  A COMPLETE ANGLE is 360°, or a full circle

• Label the angle.

  Hints

  An acute angle has a small arc of less than 90°.

  An obtuse angle has a large arc of more than than 90° and less than 180°.

  A complete angle is 360°

  Solution

  A right angle is the most common angle and forms a perfect square at the corner of the arc. Its arc is 90°

• Name and define the angles.

  Hints

  This is an obtuse angle because it is greater than 90° and less than 180°.

  A straight angle is also known as a line.

  A complete circle is 360°.

  Solution

  • A right angle is 90°
  • An acute angle is less than 90°
  • An obtuse angle is greater than 90° and less than 180°
  • A straight angle is 180°
  • A reflex angle is greater than 180° and less than 360°
  • A complete angle is 360°