The height of a triangle is the straight line drawn from the vertex perpendicular to the base.ġ2. The vertex angle of a triangle is the angle opposite the base.ġ1. A scalene triangle has three unequal sides.ġ0. An isosceles triangle has two equal sides. An equilateral triangle has three equal sides. A regular polygon has equal sides and equal angles.ġ9. A square is a quadrilateral in which all the sides are equal, and all the angles are right angles.ġ8. A triangle is bounded by three straight lines, a quadrilateral by four, and a polygon by more than four straight lines.ġ7. Rectilinear figures are figures bounded by straight lines. Angles are supplementary (or supplements of one another) if together they equal two right angles.ġ6. Angles are complementary (or complements of one another) if together they equal a right angle. An obtuse angle is greater than a right angle.ĥ. Then each of those angles is called a right angle Īnd the straight line that stands on the other is called a perpendicular to it. If a straight line that stands on another straight line makes the adjacent angles equal, The point at which two lines meet is called the vertex of the angle.ġ3. An angle is the inclination to one another of two straight lines that meet.ġ2. We will follow each with a brief commentary. They fall into three categories: Definitions, Postulates, and Axioms or Common Notions. Which is to say, the statements we do not prove should be as few as possible. Nevertheless, we should prove as many statements as possible. I T IS NOT POSSIBLE to prove every statement we saw that in the Introduction. Axioms: First principles of plane geometry
0 kommentar(er)
