Check the picture below.
now, notice the triangles made, 3 right triangles with legs of 5 and 4 each.
looking at quadrilateral (1), from the leg 5 units long, we have a line with a run of -1 and a rise of 3, from the leg 4 units long, we have a line with a run of 4 and a rise of -1.
Now, quadrilaterals (2) and (4) display the same lengths and rise and runs, which means they're all congruent, quadrilateral (3) has no equal.
so 1 ≅ 2 and 1 ≅ 4.
