Rigor : Identify tangents, secants, and chords and use properties of tangents to solve problems. Relevance: Solve problems involving planets

Example 1: Identify each line or segment that intersects P. chords: secant: tangent: diameter: radii:

A common tangent is a line that is tangent to two circles. Draw a radius from each circle’s center to the point of tangency. What do you notice?

Either write down the theorem below, or turn in your workbook to page 495 and highlight this theorem Note: The converse of this theorem is also true!

Example 2: Space Early in its flight, the Apollo 11 spacecraft orbited Earth at an altitude of 120 miles. What was the distance from the spacecraft to Earth’s horizon rounded to the nearest mile? The radius of the Earth is about 4000 miles.

Example 3: View from the Summit Kilimanjaro, the tallest mountain in Africa, is 19,340 ft tall. What is the distance from the summit of Kilimanjaro to the horizon to the nearest mile? 5280ft : 1 mile

Last concept for this section!

Example 4: HK and HG are tangent to F. Calculate HG.

12-1 Classwork (not graded) Textbook pg 797 – 799 Honors: 10, 12, 14, 15, 26, 27, 31, 35 Standard: 10, 12, 14, 15, 26, 27