Perimeter, Area and Volume - Area of a Triangle (3) - Worksheet

The worksheet titled "Area of a Triangle (3)" is designed to enhance students' fluency and precision in measuring the area of triangles. It aligns with the National Curriculum objective that requires students to recognise when they can apply formulae for the area and volume of shapes, specifically parallelograms and triangles. The resources provided for this lesson include differentiated sheets and teaching slides to cater to varying levels of student ability. The vocabulary for the lesson encompasses terms such as approximate, area, triangle, square, length, perpendicular, and formula. Students are encouraged to extend their understanding of calculating the area of right-angled triangles to any type of triangle using the formula base × perpendicular height ÷ 2. They will apply this formula to a variety of triangles with different side lengths and even to shapes composed of multiple triangles.

Throughout the lesson, key questions guide students to explore the meaning of perpendicular and its significance in determining the perpendicular height for calculating the area. They are tasked with selecting the correct calculations for the area of a triangle given the formula and the necessary dimensions. The worksheet includes examples with specific dimensions provided in centimetres, millimetres, and metres, and students must choose the appropriate calculation to find the area. Additionally, the worksheet offers reasoning and problem-solving exercises where students evaluate different methods used to calculate the area of a triangle, identifying correct approaches and explaining any errors. The errors typically arise from not selecting lengths that are perpendicular to each other. The worksheet concludes with answers to the problems, reinforcing the correct application of the formula and the importance of understanding the geometric properties of triangles.