Mon Prof Augmenté
Triangle and Rectangle
A rectangle can be split along a diagonal into two equal triangles. The area of one triangle is half the area of the rectangle.
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Age 12: open this week
Browse Age 12
In the picture
- White triangular half: half the area of the rectangle.
- Blue triangular half: the other half of the rectangle’s area.
- Diagonal crease: the line that divides the rectangle into two equal halves.
- Bottom edge: the base of the rectangle and of each triangle.
Examples
- A rectangular slice of bread cut corner to corner into two triangular sandwiches.
- A rectangular garden bed divided by a diagonal path into two triangular flower beds.
Key takeaways
- A diagonal cuts a rectangle into two triangles of equal area.
- Triangle area is half the rectangle with the same base and height: base × height ÷ 2.
Carry on in the app
Three questions on this lesson. It has left the free week, so its quiz is for subscribers.
At least one new illustrated lesson every weekday for your child’s year, with its quiz and a reminder at 6:15 pm.
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