Slope is the steepness of the surface element. Usually, the ratio of the vertical height h to the horizontal distance l of a slope is called the slope (or the slope ratio), which is represented by the letter I, that is, the tangent value of the slope angle. There are four methods to express slope: percentage method, degree method, density method and fraction method, among which percentage method and degree method are more commonly used.
The most commonly used method to express slope, that is, the percentage of the height difference between two points and their distance, is as follows: slope = (height difference/distance) x 100%. With regard to the classification of slopes used to divide slopes in detailed geomorphological drawings, it is stipulated that 0 ~ 0.5 is plain and > 0.5 ~ 2 is micro-slope. 2 ~ 5 is gentle slope, > 5 ~15 is steep slope, >15 ~ 35 is steep slope.
Pythagorean Theorem: Predicate Pythagorean Theorem is a theorem about the middle edge of a right triangle, and it is a basic theorem in mathematics. It is also called Pythagoras theorem in the west. Pythagorean Theorem and Its Inverse Theorem 1 Pythagorean Theorem: The sum of squares of two right angles of a right triangle is equal to the hypotenuse.