相似三角形是全等三角形内容的延伸．结合图形弄清相似三角形的性质定理及判定定理的条件、结论是正确解题的前提．现举例如下：例１已知：如图１，△ABC中，P为AB上一点，在下列四个条件中：①∠ACP＝∠B；②∠APC＝∠ACB；③AC２＝AP·AB；④AB·CP＝AP·CB．其中能满足△APC Similar triangles are extensions of congruent triangles. Combining graphs to clarify the nature of the similar triangle theorem and the conditions of the theorem, the conclusion is the premise to solve the problem correctly. The following is an example: Example 1 is known: Figure 1, △ ABC, P is a point AB, in the following four conditions: 1 ∠ ACP = ∠ B; 2 ∠ APC = ∠ ACB; 3AC2 = AP AB AB; 4AB·CP=AP·CB. Which can meet △APC