Cách sử dụng
'Perpendicular' means something that is at a right angle to something else. For example, if you imagine a square, the lines that run down the sides of the square are perpendicular to the lines that run across the top and bottom of the square. We might use the word 'perpendicular' to describe a pole that is standing straight up in the ground, or a wall that meets the ceiling at a right angle. It's important to pay attention to 'perpendicular' in math and geometry, as it describes the angles between lines and shapes.