Question

how can I use manipulative and nets to help compute the surface areas of rectangular and triangular prisms and pyramids​

Answer 1

For example, if the length of one side of the cube 4 units then the area of one its face is 4 × 4 = 16 square units.

From the net, we can see that there are six equal faces and so we get the total surface area is 6 × 16 = 96 square units.

Hope this helped at all, if you could copy and paste what I put as your answer.