The first volume of the fifth grade book only changed the cube into a cuboid. The drawing method of a cuboid: draw a parallelogram on it and a connected rectangle at the bottom of the parallelogram.
If there is a "progress bar" in the pictures of cuboids and cubes in the fifth grade math book, please wait patiently. If it takes too long, please refresh the page and reload.
Difficulties: How to determine the point M? Because the side lengths of the left right-angled triangle are 3, 4 and