The total surface area of the prism is made up of two congruent triangles and three differently sized rectangles. This may be shown by a net of the prism. Image caption, First work out the area of ...

The area of the base is \(5 \times 5 = 25~cm^2\) The area of each triangular face is \((5 \times 6) \div 2 = 15~cm^2\). There are four identical triangular faces, so the total surface area is \(25 ...