4: Similar Triangles
- Page ID
- 34134
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- 4.1: Proportions
- In our discussion of similar triangles the idea of a proportion will play an important role. In this section we will review the important properties of proportions.
- 4.2: Similar Triangles
- Two triangles are said to be similar if they have equal sets of angles.
- 4.3: Transversals to Three Parallel Lines
- Previously, we defined a transversal to be a line which intersects two other lines, We will now extend the definition to a line which intersects three other lines.
- 4.4: Pythagorean Theorem
- In a right triangle, the square of the hypotenuse is equal to the sum of the squares of the legs.
- 4.5: Special Right Triangles
- There are two kinds of right triangle which deserve special attention: the 30°−60°−90° right triangle and the 45°−45°−90° right triangle.
Thumbnail: Similar Triangles. (CC BY-SA 3.0; Nguyenthephuc via Wikipedia).