Figure 3 shows two line segments AB and AC intersecting at the point A . Construct two circles of different sizes between them such that (i) they touch each other at a point; and (ii) the lines AB and AC are tangents to both circles. 圖三所示為兩相交於 A 點的線段 AB 及 AC 。 試在它們之間構作兩個大小不同的圓使得 (i) 該兩圓相交於一點；及 (ii) 線段 AB 和 AC 均為該兩圓的切線。