First: I want to note that the task was not set correctly.
How the task was actually supposed to be written:
The length of the chord from the center of the circle is 45 cm (for example) Find the diameter of this circle
In fact, this task is very quickly and easily solved.
Let’s imagine a circle. It is known that a circle is a geometric figure (closed curve) consisting of many points equidistant from the center of this circle. Draw a chord passing through the center of the circle (a chord is a segment connecting any two points on the circle). As you know, the chord length is 45 (cm). So there is a statement that: “The chord drawn through the center of the circle is the diameter of this circle.” From here comes our decision that the chord equal to 45 (cm) is the diameter of the circle. Q.E.D!
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