2 Angular Axiom (SAS) has two triangles with equal angles.
The Axiom of Triangle (ASA) has the congruence of two triangles, which have two angles and their sides correspond to each other.
4 Inference (AAS) has two angles, and the opposite side of one angle corresponds to the congruence of two triangles.
The pentagonal axiom (SSS) has two triangles with equal sides.
6 Axiom of hypotenuse and Right Angle (HL) Two right angle triangles with hypotenuse and right angle are congruent.
Theorem 7 1 The distance between a point on the bisector of an angle and both sides of the angle is equal.
Theorem 2: The points with equal distance on both sides of an angle are on the bisector of this angle.
The bisector of angle 9 is the set of all points with equal distance to both sides of the angle.
The property theorem of 10 isosceles triangle: the two base angles of isosceles triangle are equal (that is, equilateral and equilateral).
2 1 Inference 1 The bisector of the vertices of an isosceles triangle bisects the base and is perpendicular to the base.
The bisector of the top angle, the median line on the bottom edge and the height on the bottom edge of the isosceles triangle coincide with each other.
Inference 3 All angles of an equilateral triangle are equal, and each angle is equal to 60.
24 Judgment Theorem of an isosceles triangle If a triangle has two equal angles, then the opposite sides of the two angles are also equal (equal angles and equal sides).
Inference 1 A triangle with three equal angles is an equilateral triangle.
Inference 2 An isosceles triangle with an angle equal to 60 is an equilateral triangle.
In a right triangle, if an acute angle is equal to 30, the right side it faces is equal to half of the hypotenuse.
The center line of the hypotenuse of a right triangle is equal to half of the hypotenuse.
Theorem 29 The distance between the point on the vertical line of a line segment and the two endpoints of this line segment is equal.
30 inverse theorem and the point where the distance between the two endpoints of a line segment is equal is on the middle vertical line of this line segment.
The perpendicular bisector of 3 1 line segment can be regarded as the set of all points with equal distance from both ends of the line segment.
Theorem 32 1 Two graphs symmetric about a line are conformal.
Theorem 2: If two figures are symmetrical about a straight line, then the symmetry axis is the perpendicular line connecting the corresponding points.
Theorem 3 Two graphs are symmetrical about a straight line. If their corresponding line segments or extension lines intersect, then the intersection point is on the axis of symmetry.
35 Inverse Theorem If the straight line connecting the corresponding points of two graphs is bisected vertically by the same straight line, then the two graphs are symmetrical about this straight line.
36 Pythagorean Theorem The sum of squares of two right angles A and B of a right triangle is equal to the square of the hypotenuse C, that is, A 2+B 2 = C 2.
37 Inverse Theorem of Pythagorean Theorem If the three sides of a triangle A, B and C are related in length A 2+B 2 = C 2, then the triangle is a right triangle.
The sum of the quadrilateral internal angles of Theorem 38 is equal to 360.
The sum of the external angles of a 39 quadrilateral is equal to 360.
Theorem of the sum of internal angles of 40 polygons The sum of internal angles of n polygons is equal to (n-2) × 180.
4 1 It is inferred that the sum of the external angles of any polygon is equal to 360.
42 parallelogram property theorem 1 parallelogram diagonal equality
43 parallelogram property theorem 2 The opposite sides of parallelogram are equal
It is inferred that the parallel segments sandwiched between two parallel lines are equal.
45 parallelogram property theorem 3 diagonal bisection of parallelogram.
46 parallelogram decision theorem 1 Two groups of parallelograms with equal diagonals are parallelograms.
47 parallelogram decision theorem 2 Two groups of parallelograms with equal opposite sides are parallelograms.