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Why is the radius 4?



Why is the radius 4? ​-example-1
User Frage
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Answer:

Please check explanations

Explanation:

The equation of a circle can be represented as;

(x-h)^2 + (y-k)^2 = r^2

r is the radius while (h,k) represents the coordinates of the center

Thus, we have that;

(x-2)^2 + (y+3)^2

That would give;

x^2 - 4x + 4 + y^2 + 6y + 9

The sum of values with no coefficient is;

4 + 9 = 13

If we take this to the other side, we can have 13 + 3 = 16

The square root of this is then 4

Mathematically, we can therefore express the equation of the circle as;

(x-2)^2 + (y-+3)^2 = 4^2

By expansion, we will get the original given equation

User Inetphantom
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