The distance between the two points has a linear relationship
with the lengths of the segments. So if we dilate the circle with a scale
factor of 3, the distance between the two would also be dilated with a scale
factor of 3. Therefore let us first find for the distance or length of CB. The
distance formula is:
d^2 = (x2 – x1)^2 + (y2 – y1)^2
where:
C = (x1, y1) = (8, 10)
B = (x2, y2) = (12, 13)
Therefore the length of CB is:
d^2 = (12 – 8)^2 + (13 – 10)^2
d^2 = 25
d = 5
Therefore the length of C’B’ is 3 times of this since dilation means expansion:
C’B’ = 5 * 3 = 15
