1. Day 19 AGENDA: DG 10 --- 15 minutes
Workday on CLT & Conf Int min
Begin Unit Algebra Topics

3. Unit #2: Algebra Topics Lesson 1: Review of Circles
Accel Precalculus
Unit #2: Algebra Topics Lesson 1: Review of Circles
EQ: What is the equation of a circle and how do you use it to graph a circle?

4. (h, k) r Conic Sections in Algebra:
Circle --- the set of all points in a plane that are a common distance , called the radius, from a fixed point, called the center.
(h, k)
center: _________ r
radius: ______

5. An equation for the circle with its center at
Standard Equation of a Circle:
An equation for the circle with its center at
(0, 0) and a radius of r is
Standard Equation of a Translated Circle:
The standard equation for circle with its center
at (h, k) and a radius of r is

8. Ex A cell phone tower is located 25 miles east and 30 miles south of Lorne’s home. The tower’s signal is strong enough to reach phones within a 50 miles radius. Write the equation that represents all ground locations 50 miles from the cell phone tower given that Lorne’s home is located at (0,0).

9. Can a person living 10 miles east and 5 miles north of Lorne receive the tower’s signal?
Houses receiving phone reception are
found using the following inequality.
WHY?
The person’s home located 10 miles east and
5 miles north must be located within this circle.

10. RECALL: COMPLETING THE SQUARE

12. In class practice.
1. Write the standard form of the circle graphed at the right.

13. 2. Graph (x - 1)2 + (y - 5)2 = 4

14. (3, 4) 6 (3, 2) 5 3. Find the center and radius of the circle with the
given equation. a.
(3, 4) 6
center: _________ radius: ______ b.
center: _________ radius: ______
(3, 2) 5

15. ASSIGNMENT :
Worksheet: Review of Circles
#9, 10, 12, 17, 19, 28, 44, 47, 49, 68, 73, 78