Circles Diameter Chord Central Angle Semicircle Tangent Inscribed Angle R10 Radius Secant Major Arc Minor Arc Angle Rules Central O Rule: ____________________ Inscribed .O 1 Rule: ____________________ .O 2 Tangent and a Chord .O Rule: ____________________ Arcs and Parallel Chords Intersecting Chords .O Rule: __________________ Rule:_______________ Tangents and Secants Rule:____________________ A Tangent and a Secant . O Two Tangents .O Two Secants .O R10 1. In the diagram below, trapezoid ABCD, with bases with diameter 2. . If In the diagram below of circle O, chords In the diagram below of circle O, chords ABC 28 and , is inscribed in circle O, , find ADC . . What is the degree measure of 3. and and intersect at E, , and ? and intersect at point B, such that ª ? . What is AC x 28 R10 4. In the diagram below, tangent is 5. . Find , what is are drawn to circle O. The ratio . In the diagram of circle O below, chords of the circle. If 6. and secant and are parallel, and is a diameter ? In the diagram below, two parallel lines intersect circle O at points A, B, C, and D, with and . Find . R10 Length Rules C Intersecting Chords A E B Rule:_______________________ D Common Tangents Rule:_______________________ Lengths of Tangents and Secants Two Secants Tangent and a Secant Rule:____________________ Rule:_______________________ 1. In the diagram of circle O below, chord intersects chord , , and . What is the value of x? at E, , R10 2. In the diagram below of circle O, diameter If and , find the length of . is perpendicular to chord 3. In the diagram below of circle O, chord bisects chord find the length of in simplest radical form. 4. In the diagram below of circle O, radius is 5 cm. Chord is 8 cm and is perpendicular to at point P. What is the length of , in centimeters? at E. If and at E. , R10 5. How many common tangent lines can be drawn to the two externally tangent circles shown below? 6. In the diagram below, respectively, , 7. 8. , , and , and are tangents to circle O at points F, E, and D, . What is the perimeter of ? In the diagram below, circles X and Y have two tangents drawn to them from external point T. The points of tangency are C, A, S, and E. The ratio of TA to AC is 1:3. If TS = 24, find the length of SE. In the diagram below, tangent and secant are drawn to circle O from external point P. If and , what is the length of ? R10 9. In the diagram below of circle O, chords tangent , 10. and intersect at M. Secant and are drawn to circle O. The length of is two more than the length of , , and . Find the length of . Find the length of . In the diagram below of circle O, secant intersects circle O at E, , of ? Equations of Circles intersects circle O at D, secant , and . What is the length r (h,k) R10 Center at the origin (0,0) with radius r units. _________________ 1. Center at the point (h, k) with radius r units. _________________ What are the center and the radius of the circle whose equation is ? 2. Write an equation for each circle whose center is (-3, 2) and whose diameter is 10. 3. Write an equation represents the circle whose center is 4. A circle is represented by the equation . What are the coordinates of the center of the circle and the length of the radius? 5. Write an equation for the circle shown in the graph below? and whose radius is 5? R10 6. Write the equation represents circle K shown in the graph below? 7. Write an equation of the circle graphed in the diagram below. 8. What is an equation of a circle with its center at and a radius of 4?