三角形与平行四边形的面积
Area of Triangles & Parallelograms
使用公式计算平行四边形和三角形的面积（平行四边形：面积 = 底 × 高；三角形：面积 = ½ × 底 × 高）
Calculate the area of parallelograms and triangles using formulae (A = b × h for parallelograms, A = ½ × b × h for triangles)
学习证据 / Evidence
- 计算底为 8 厘米、高为 5 厘米的平行四边形的面积
- 计算底为 12 厘米、高为 7 厘米的三角形的面积
- 解释为什么三角形的面积是相关平行四边形面积的一半
- Calculate the area of a parallelogram with base 8 cm and height 5 cm
- Calculate the area of a triangle with base 12 cm and height 7 cm
- Explain why the area of a triangle is half the area of a related parallelogram
评估问题 / Assessment
如果{{name}}在裁剪三角形布料，每块布料的底为 8 厘米，高为 5 厘米，能否用公式算出每块布料的面积？
If {{name}} is cutting triangular pieces of cloth where the base is 8 cm and the height is 5 cm, can they use a formula to work out the area of each piece?