1. Examples: Intro to Conics - Circles
Find the radius.
1) x2 + y2 = 25
2) x2 + y2 = 12
3) x2 + y2 = 80

2. Examples: Intro to Conics - Circles
Graph the equation. Identify the radius.
4) x2 + y2 = 81
5) x2 + y2 = 72

3. Examples: Intro to Conics - Circles
Write these circles in standard form. State the radius.
6) 5x2 = y2
7) -6x2 = y2
8) 7y2 + 7x2 -21 = 0

4. Examples: Intro to Conics - Circles
Write the standard form of the equation of the circle with the given radius and whose center is the origin.
9) 6
10)
11)