Open Middle®
Directions: Using the integers -9 to 9, at most one time each, place an integer in each box to create a circle and a point on the circle.
Hint
How can you use the values being subtracted from x and y to adjust where the circle is?
For an interactive conceptual version of this problem created in GeoGebra, click here.
Answer
There are many potential answers but all will come from a circle with a radius of 5 units including:
(x – -2)^2 + (y – -1)^2 = 5^2
Point on circle: (-6, -4)
(x – -2)^2 + (y – -1)^2 = 5^2
Point on circle: (-6, -4)
(x – -2)^2 + (y – -1)^2 = 5^2
Point on circle: (1, 3)
Source: Robert Kaplinsky