Book:Euclid/The Elements/Book VI

Contents

 * Book VI: Theory of Proportions as applied to Plane Geometry
 * Definitions
 * Proposition 1: Areas of Triangles and Parallelograms Proportional to Base
 * Proposition 2: Parallel Line in Triangle Cuts Sides Proportionally
 * Proposition 3: Median Cuts Base in Same Ratio as Remaining Sides
 * Proposition 4: Equiangular Triangles are Similar
 * Proposition 5: Triangles with Proportional Sides are Similar
 * Proposition 6: Triangles with One Equal Angle and Two Sides Proportional are Similar
 * Proposition 7: Triangles with One Equal Angle and Two Other Sides Proportional are Similar