AMSCO'S Geometry. New York - Rye High School

26 Essentials of GeometryRight TrianglesIn right triangle GHL, the two sides of the trianglethat form the right angle, GH and HL, are called thelegs of the right triangle. The third side of the triangle,GL, the side opposite the right angle, is calledthe hypotenuse.legGhypotenuseH leg LEXAMPLE 1EIn DEF,mE 90 and EF ED.DFAnswersa. Classify the triangle according The triangle is an isosceles triangle.to sides.b. Classify the triangle according The triangle is a right triangle.to angles.c. What sides are the legs of The legs of the triangle are EFthe triangle? and ED.d. What side is opposite the right FD is opposite the right angle.angle?e. What angle is opposite EF? Angle D is opposite EF.f. What angle is included between Angle F is between EF and FD.EF and FD?Using Diagrams in GeometryIn geometry, diagrams are used to display and relate information. Diagrams arecomposed of line segments that are parallel or that intersect to form angles.From a diagram, we may assume that:• A line segment is a part of a straight line.• The point at which two segments intersect is a point on each segment.• Points on a line segment are between the endpoints of that segment.• Points on a line are collinear.• A ray in the interior of an angle with its endpoint at the vertex of theangle separates the angle into two adjacent angles.From a diagram, we may NOT assume that:• The measure of one segment is greater than, or is equal to, or is less thanthat of another segment.• A point is a midpoint of a line segment.