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Find the center and radius of the circle x^2+y^2-10x-12y+45=0.

User Obinna Kalu
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1 Answer

18 votes
18 votes

Answer:

The center is (5, -6) with a radius of r

Explanation:

First put the equation in Standard Form for a circle:

(x + a)² + (y + b)² = r²

Now, Group the term

x² + y² - 10x - 12y + 45 = 0

x² - 10x + y² - 12y = - 45

Then, The x and y terms must be perfect squares

x² - 10x + 25 + y² - 12y + 36 = - 45 + 25 + 36

add constant both sides we get,

x² - 10x + 25 + y² - 12y + 36 = 16

Now, Simplify

(x - 5)² + (y + 6)² = 16

√(x - 5)² + (y + 6)² = √16

x - 5 + y + 6 = 4

Here, (a,b) = (5, -6) and = 16, with r = 4

Thus, The center is (5, -6) with a radius of r

-TheUnknownScientist 72

User Nandish
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