In Figure 5, if OX = OY, then by Theorem 82, AB = CD.įigure 5 A circle with two minor arcs equal in measure.Įxample 3: Use Figure 6, in which m = 115°, m = 115°, and BD = 10, to find AC.įigure 6 A circle with two minor arcs equal in measure.Įxample 4: Use Figure 7, in which AB = 10, OA = 13, and m ∠ AOB = 55°, to find OM, m and m. Theorem 82: In a circle, if two chords are equidistant from the center of a circle, then the two chords are equal in measure. In Figure 4, if AB = CD, then by Theorem 81, OX = OY.įigure 4 In a circle, the relationship between two chords being equal in measure and being equidistant from the center. Theorem 81: In a circle, if two chords are equal in measure, then they are equidistant from the center. įigure 3 A diameter that is perpendicular to a chord. In Figure 3, UT, diameter QS is perpendicular to chord QS By Theorem 80, QR = RS, m = m, and m = m. Theorem 80: If a diameter is perpendicular to a chord, then it bisects the chord and its arcs. These theorems can be used to solve many types of problems. Some additional theorems about chords in a circle are presented below without explanation. (b) If m = and EF = 8, find GH.įigure 2 The relationship between equality of the measures of (nondiameter) chords and equality of the measures of their corresponding minor arcs. Theorem 79: In a circle, if two minor arcs are equal in measure, then their corresponding chords are equal in measure.Įxample 1: Use Figure 2 to determine the following. The converse of this theorem is also true. Theorem 78: In a circle, if two chords are equal in measure, then their corresponding minor arcs are equal in measure. This is stated as a theorem.įigure 1 A circle with four radii and two chords drawn. This would make m ∠1 = m ∠2, which in turn would make m = m. In Figure 1, circle O has radii OA, OB, OC and OD If chords AB and CD are of equal length, it can be shown that Δ AOB ≅ Δ DOC. Summary of Coordinate Geometry Formulas. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |