1, first observe the number of data groups given by the topic. Generally, you will find regular questions in the senior high school entrance examination, and you will not be given more than 4 groups of data.

2. If it is three groups of data, we should consider the linear function relationship (y=kx(+b)) and the inverse proportional function relationship (y=k/x). Substitute the first two groups of data into these two functional relationships (first function, then inverse proportional function). Then it is verified by the corresponding data given by the third group, which is generally true.

3, if it is four groups of data, we should consider the quadratic function relationship (y=ax? (+bx+c))。 Find the values of a, b and c respectively, and then bring the fourth set of data into verification.

4. If it is five sets of data, it shows that this problem is very difficult, just skip it and don't waste time.

Second, the problem of folding.

1. If it is a multiple-choice question, it won't be difficult. You can fold it directly with draft paper, and the answer will be easy to find.

2. If it is a solution such as proof, you must do the following:

(1) Grasp the invariants, especially the degree of angle and the length of line segment;

(2) It can be used as an auxiliary line, which mainly includes three points: ① After folding, two overlapping points are connected, so the crease must be the middle vertical line of this line; ② Rotation, which is difficult, needs to prove similarity or congruence; ③ Reverse extension to construct a special quadrilateral.

Do the above, I believe that you will have a good idea if you encounter this kind of problem again in the senior high school entrance examination. Of course, I just graduated, and all these points are summarized on the basis of my teacher.