Math

posted by .

The equation of a circle is x^2-6x+y^2+2y=15
what is the center and the radius?

  • Math -

    factor it as perfect squares

    x^2-6x + 9 + y^2+2y + 1= 15+9+1
    (x-3)^2 + (y+1)^2=25
    so center is 3,1 and radius is 5

  • Math -

    oops, center 3,-1

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. math

    Write an equation of a circle with the center (-5,-4) and radius 6. The general equation for a circle is (x-a)^2 + (y-b)^2 = r^2, where r is the radius of the circle and (a,b) are the (x,y) coordinates of the center. Make the appropriate …
  2. math

    a circle is tangent to the y-axis at y=3 and has one x-intercept at x=1 a) what's the other x-intercept b) what's the equation i have no clue how to solve this! You know that the center of the circle is somewhere in the line y = 3, …
  3. Math

    The points (4, –5) and (– 4, 1) are endpoints of a diameter of a circle. (a) Find the center of the circle. (b) Find the length of the radius of the circle. (Note that this is a distance.) Give the exact answer. Show work. (c) …
  4. Math(Please check answers)

    These questions that I have completed are on a test review for my exam and I would just like to know if they are correct. These are only a few of the questions, I have more that are just not complete yet. Thank You! 1) List the intercepts …
  5. Math

    These questions that I have completed are on a test review for my exam and I would just like to know if they are correct. These are only a few of the questions, I have more that are just not complete yet. Thank You! 1) List the intercepts …
  6. NEED MAJOR HELP! *QUADRATIC EQUATIONS*

    Write the equation for the circle with center at (- 8, - 6) and radius of 10. (x+8)² + (y + 6)² = 10 (x+8)² + (y + 6)² = 100 (x-8)² + (y - 6)² = 100 Find the standard equation for the circle with center on the positive x-axis …
  7. college pre-calculus

    4x^2+4y^2-16x-24y+51=0 is the equation of a circle. where is the center of the circle and what is it's radius?
  8. math

    4x^2+4y^2-16x-24y+51=0 is the equation of a circle. where is the center of the circle and what is it's radius?
  9. math

    4x^2+4y^2-16x-24y+51=0 is the equation of a circle. where is the center of the circle and what is it's radius?
  10. Geometry

    Write the General form equations for the following circles: 1. A circle with center (1, -6) and radius 4 2. A circle with center (6, 8) and radius 10 3. A circle with center (0, 3) and radius 2√3 4. A circle with center (-0.5, 5.5 …

More Similar Questions