Determination of triangle congruence (1)

Determination of Triangle Congruence (3)

Determination of Triangle Congruence (2)

Proof of the theorem of sum of internal angles of triangles: paying attention to the external angles of triangles.

Proof of the theorem of sum of interior angles of triangle

Sum of internal angles of triangle

Judgement of triangle similarity

Centrally symmetric graphs and centrosymmetric graphs

Centrally symmetric figure

Example of drawing problem

Congruent triangle

Congruent triangles Test (Volume A)

Congruent triangles Test (Volume B)

Some Concepts about Triangle

Pay attention to the outer corner of the triangle.

pythagorean theorem

quadrilateral

Magnification and reduction of graphics

Sum of interior angles of polygons

Parallelogram and its properties

Discrimination of parallelogram

Properties of parallelogram

Parallel bisection theorem

Figures with the same shape are similar to polygons.

Graphics of the same shape

Explore the conditions of triangle similarity and measure the height of flagpole.

Explore the conditions of triangle similarity (1)

Exploring the Conditions of Triangle Similarity (2)

Explore the sum of inner and outer angles of polygons

Explore the inner angle of polygon and use the outer angle to closely lay with plane figure.

trapeziform

square

Determination of congruence of right triangle

similar triangles

The nature of similar triangles

similar polygons

Perimeter ratio and area ratio of similar polygons

Properties of Similar Polygons —— Magnification and Reduction of Graphics

Rectangular, rhombic

Determination of isosceles triangle

Properties of isosceles triangle

Perpendicular bisector of line segment

Can you get a right triangle?

internal bisector

Drawing test of bisector of angle and ruler (Volume A)

Drawing test of angle bisector and square ruler (Volume B)

Axisymmetric and axisymmetric graphs