Name_________________________ Math 9 - Unit 8 Circle Geometry - PRETEST 1. Which statement is true? A. B. C. D. A central angle is smaller than an inscribed angle subtended by the same arc. Two inscribed angles are never equal in size. An inscribed angle subtended by a diameter of the circle is always 90°. An inscribed angle in a semicircle can be larger than 90°. 2. What is the measure of the inscribed angle? A. B. C. D. 25° 50° 100° 200° 3. Determine the measure of each angle. a) <ABD b) <ACD 4. What are the measures of the unknown angles of x and y? 5. What is the measure of <EFG? Describe the circle property used. 6. What is the measure of <BAD in the semicircle? 7. What is the measure of <FCG if DE is tangent to the circle? 8. If AB is tangent to the circle at B, what is the length of the radius? 9. Find the length of EF 10. If AB is tangent to the circle, find the measure of <BCD. 11. What is the length of radius x? Express your answer to the nearest tenth of a centimetre. 12. Find the measure of angle θ. Line l is tangent to the circle. 13. What are the measures of <ADB and <ACB? Explain your reasoning. 14. The diagram represents the water level in a pipe. The surface of the water from one side of the pipe to the other measures 20mm, and the inner diameter of the pipe is 34mm. What is the shortest distance from the centre of the pipe to the water level, rounded to the nearest millimetre? Explain your reasoning.