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Please help me to solve the question!​

Please help me to solve the question!​-example-1
User Juanillo
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1 Answer

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Answer: (x - 3)² + (y + 0.5)² = 3.25 →
(x-3)^2+\bigg(y+(1)/(2)\bigg)^2=(13)/(4)

Explanation:

Concentric means they have the same center but different radii.

The equation of a circle is: (x - h)² + (y - k)² = r² where

  • (h, k) is the center of the circle
  • r is the radius of the circle

Complete the square to find the center of the circle

x² - 6x + _____ + y² + y + _____ = 1 + ____ + ____

↓ ↓

-6/2 = -3 1/2 = 1/2

Equation: (x - 3)² + (y + 1/2)² = r²

Since the circle passes through point (x, y) = (4, -2), input that into the equation to find r².

(x - 3)² + (y + 1/2)² = r²

(4 - 3)² + (-2 + 1/2)² = r²

(1)² + (-3/2)² = r²

1 + 9/4 = r²

13/4 = r²

Equation: (x - 3)² + (y + 1/2)² = 13/4 →
(x-3)^2+\bigg(y-(1)/(2)\bigg)^2=(13)/(4)

In decimal form: (x - 3)² + (y + 0.5)² = 3.25

User Janne Oksanen
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