1.   The equation of a circle is 3x2 + 3y2 – 6x + 12y – 24 = 0. Write the standard form of the equation.
    A.
    B. (x – 1)2 + (y – 2)2 = 13
    C.
    D. (x – 1)2 + (y + 2)2 = 13
    Hint

  2.   The equation of a circle is 3x2 + 3y2 – 6x + 12y – 24 = 0. Find its center and radius.
    A. (–1, 2); 13 B. (–1, 2);
    C. (1, –2); 13 D. (1, –2);
    Hint

  3.   Write the equation of a circle that passes through the origin and has its center at (–3, –2).
    A. (x + 3)2 + (y + 2)2 = 13
    B. (x – 3)2 + (y – 2)2 = 13
    C. (x – 3)2 + (y + 2)2 = 10
    D. (x + 3)2 + (y + 2)2 = 5
    Hint

  4.   Write the equation of the circle whose diameter has endpoints at (3, –1) and (–9, 5).
    A. (x + 3)2 + (y – 2)2 = 13
    B. (x + 3)2 + (y – 2)2 = 45
    C. (x – 3)2 + (y + 2)2 = 45
    D. (x – 3)2 + (y + 2)2 = 13
    Hint

  5.   Write the equation of the circle that is tangent to the line with equation
x + y = –3 and has its center at (4, –1).
    A. B. (x – 4)2 + (y + 1)2 = 18
    C. (x + 4)2 + (y – 1)2 = 18 D.
    Hint



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