Area of an isosceles triangle
An isosceles triangle is drawn on a grid where each block is 1 cm². The student finds its area.
The height runs from the top corner straight down to the middle of the base, so it can be read off the grid. The area is half of base × height.
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What changes each time
- Corners on a 16 × 16 grid
- Tall and short, wide and narrow triangles
- A new triangle every time
More area, perimeter and volume practice
- Area by counting squares (Grade 2)
- Area and perimeter of a square (Grade 3)
- Area and perimeter of a rectangle (Grade 3)
- Area with half squares (Grade 3)
- Area of an L-shape (Grade 3)
- Perimeter of an L-shape (Grade 3)
- Draw a rectangle with a given area and perimeter (Grade 3)
- Missing side of a rectangle (Grade 4)
- Rectangle sides from a ratio (Grade 4)
- Area of a right triangle (Grade 4)
- Area of a scalene triangle (Grade 4)
- Area of an irregular polygon (Grade 5)
- Missing triangle in a square (Grade 5)
- Volume by counting cubes (Grade 5)