A right angle looks like the corner of a sheet of paper.
Here's how:
1. Look closely at every corner of the figure.
2. Check with a paper corner or a set square whether the corner is a right angle.
3. Draw a dot in every right angle and count all the dots at the end.
The dots and numbers filled in show the solution.
Example
For parents
What does this exercise practice?
This exercise trains the eye for right angles in figures and prepares for measuring with a set square.
Common pitfalls
Children often fail to recognize right angles on slanted edges because they only look for horizontal and vertical lines. It helps to place a paper corner in the angle and turn the figure.
How to practice at home
Look for right angles around the house, for example on windows, doors, books and tiles.
Related: Tiling Areas, Mirror image, Counting Shapes