The circle passes through the point (3,6). What is it’s radius?
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Answer:
c. 5
Step-by-step explanation:
In the attached image we can calculate the radius in a very simple way, if we focus on the axis of the "y" we have that there is a distance that would be the diameter of the circle and goes from -2 to 8.
Between -2 and 8, there is a quantity of 10 units, since:
8 + 2 = 10
they are added because we want to know the total distance, therefore the diameter is 10, and we know that the radius is half the diameter, so:
r = d / 2
r = 10/2
r = 5
therefore the radius is 5 units, that is, the answer is c. 5