Activity 4: Is this a circle? Determine which of the following equations are equations of a circle. Justify your answer. 1. x2 + y2 + 4 = 0 2. x2 + y2 - 20 = 0 3. x2 + y2 + 8x + 16 = 0 4. x2 + 6x = y2 - 25 5. x² + y² – 4 = 4x – 10y 3 xtce y=-1 Guide Questions: 1. How was the activity? 2. Were you able to identify which are circles and which are not? 3. How? napaka unfair Naman po walang sumasagot Ng tanungko