There are generally two body types.

1. variant problem (geometry), as long as you find the law of 1 2, you can use the law of the third problem to find the addition of auxiliary lines, and the common addition of auxiliary lines depends on your own accumulation.

2. Understanding the reading problem (geometric algebra) is the key. If you can't understand them, read them again and again, and then contact what you have learned to answer them.

3. The combination of numbers and shapes is a common finale in the senior high school entrance examination in most areas. It is not reflected in the first grade, but will appear after learning the moving points and functions in the second grade. Not much to explain.

All the above are original, please respect my right to intellectual achievements, thank you.