An artist is creating a circular mosaic and needs to determine the x-coordinate of the center for proper layout. The boundary of the mosaic is described by the equation x2+y2+4x−6y=0

. What is the x-coordinate?(1 point)
The x-coordinate is
.

1 answer

To find the x-coordinate of the center of the circular mosaic given by the equation \( x^2 + y^2 + 4x - 6y = 0 \), we first need to rewrite this equation in standard form by completing the square.

  1. Start with the given equation: \[ x^2 + y^2 + 4x - 6y = 0 \]

  2. Rearrange the equation: \[ x^2 + 4x + y^2 - 6y = 0 \]

  3. Complete the square for \( x \):

    • For \( x^2 + 4x \), take half of 4, square it, giving \( 4 \): \[ x^2 + 4x = (x + 2)^2 - 4 \]
  4. Complete the square for \( y \):

    • For \( y^2 - 6y \), take half of -6, square it, giving \( 9 \): \[ y^2 - 6y = (y - 3)^2 - 9 \]
  5. Substitute these back into the equation: \[ (x + 2)^2 - 4 + (y - 3)^2 - 9 = 0 \] \[ (x + 2)^2 + (y - 3)^2 - 13 = 0 \] \[ (x + 2)^2 + (y - 3)^2 = 13 \]

Now we have the equation in standard form, which describes a circle: \[ (x + 2)^2 + (y - 3)^2 = 13 \] From this equation, we can identify the center of the circle at the coordinates \( (-2, 3) \).

Therefore, the x-coordinate of the center is: \[ \text{x-coordinate} = -2 \]

So the answer is \(-2\).