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Lesson 9 of 10

Track quiz

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6 min

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Here is the whole chapter on one screen. Then seven quick questions.

Lines and Angles — every angle move you now have
IdeaWhat to remember
Point, line, ray, segmentTold apart by their ends.
Two linesThey cross at one point, or they are parallel and never meet.
What is an angleThe turn between two rays with one vertex.
MeasuringA full turn is 360°. A protractor reads the size.
Kinds of anglesAcute < 90°. Right = 90°. Obtuse 90°–180°. Straight = 180°. Reflex 180°–360°.
DrawingCentre on the vertex. Mark the degree. Draw the ray.
Angles around usCompare the numbers, not the drawings.

A figure has one fixed end. The other end goes on for ever. What is it?

  • A line segment
  • A ray
  • A line

Two lines never meet, however far they go. What are they called?

  • Intersecting
  • Parallel
  • A ray

Two rays start at one point. What is that point called?

  • An arm
  • The vertex
  • A degree

How many degrees are in a full turn?

  • 180°
  • 360°
  • 90°

Two angles are both 40°. One has short arms. One has long arms. What is true?

  • The long-armed angle is bigger.
  • They are the same size.
  • The short-armed angle is bigger.

An angle is 65°. What kind is it?

  • Acute
  • Right
  • Obtuse

The clock hands make 180°. What time could it be?

  • 3 o'clock
  • 6 o'clock
  • 9 o'clock

Chapter 2, Lines and Angles, is now yours. Read it with a protractor in hand.

Next: Number Play — digits, palindromes and quick estimates.

Reveal every answer to finish this lesson.