1. Section 1.9 Distance and Midpoint Formulas; Circles

2. The Distance Formula

5. Example
Find the distance between (4,-5) and (9,-2).

6. The Midpoint Formula

7. (6,8)
(-1,5)

8. Example
Find the midpoint of the segment whose endpoints are (-1,7) and (-5,9).

9. Circles

11. Graphing Calculator

12. Write the standard form of the equation of the circle with center (-4,1) and radius of 3.

13. Find the center and radius of the circle whose equation is
Graph the equation.
Use the graph to identify the relation’s domain and range. Why is it a relation and not a function?
Center(-3,4); radius=3 3
Domain: [-6,0]; Range:[1,7]
(-3,4)

14. Example
Write the standard form of the equation of the circle with center at (-2,7) and a radius of 5.

15. Example
Find the center and radius of the circle whose equation is below. Graph the equation. Use the graph to identify the relation’s domain and range.

16. General Form

17. ? ?

18. Example
Complete the square and write the equation in standard form. Then give the center and radius of the circle and graph the equation.

19. Example
Complete the square and write the equation in standard form. Then give the center and radius of the circle and graph the equation.

20. Find the distance between the points (-1,8) and (9,5).

21. Find the midpoint of the line segment with the endpoints of (-1,-1) and (- 5,8).
(b)
(c)
(d)

22. Write the equation of the line with center at (0,7) and a radius of 4.
(b)
(c)
(d)