Rotating triangles into the same orientation, with the right-angle in the bottom right, makes it easier to visualise which two shapes are similar. Triangles ABC and DEF are similar. Triangle DEF ...

The net is made up of two right-angled triangles and three rectangles. The dimensions of the rectangles are 3 cm by 6 cm, 4 cm by 6 cm, and 5 cm by 6 cm. There are no measurements on the 3D shape.