Congruent triangles and similar triangles proved it!
First, you have to find out the conditions of triangle congruence:
Side by side SSS
SAS corner edge &; The hypotenuse and right angle of HL right triangle
ASA corner &； Corner edge
In fact, when doing congruent triangles proof, first look for what is equal, which is the angle or the edge.
If it is complicated, you will find the equilateral corner through the center line, parallel lines and other things.
Furthermore, similar triangles.
AAA, just find two corners equal.
The two sides of "SAS" are proportional and the included angle is equal.
The three sides of "SSS" are proportional.
Similar triangles proved that the topic is relatively simple.
Most of them are looking for the center line, which is probably the area.
If congruent triangles is mixed with similar triangles, the most important thing is to find out which angle is right for which angle and which side is right for that angle.
Finally, remember the nature of congruent triangles and similar triangles.
Congruent triangles has the same area and circumference.
Similar triangles's weekly growth is in direct proportion, and its area is square.