Is line symmetry the same as diagonal symmetry?

No, line symmetry and diagonal symmetry are not the same. Line symmetry, also known as reflection symmetry, occurs when a figure can be divided into two equal halves that are mirror images of each other across a line. Diagonal symmetry, on the other hand, occurs when a figure can be divided into two equal halves that are mirror images of each other across a diagonal line. In essence, while both involve symmetry across a line, the orientation and positioning of that line differ between the two types of symmetry.