Mon Prof Augmenté
The little square mark
Age 9 · Maths
When two straight lines meet at a perfect corner, a small square can fit inside. The square touches both lines and shows that the corner is a right angle.
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Age 9: open this week
Browse Age 9
Examples
- The corner of a book.
- The corner of a window frame.
Key takeaways
- A right angle is exactly 90 degrees.
- A small square in the corner is its mark.
Quiz: The little square mark (Age 9)
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A right angle is exactly how many degrees?
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Which mark shows that a corner is a right angle?
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What does the small square at a corner tell you?
The answers, each with its explanation, are in the app. This lesson has left the free week, so its quiz is part of the subscription.
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