Math

Circle

1
Center = (-2,2) (Type an ordered pair Simplify your answer.)
54. There are several ways to find the radius of the circle One way is to find the distance between the center and the point (-5,8). Use the result from part 53 and
the distance formula to find the radius
r=
315 (Type an exact answer, using radicals as needed.)
55. Another way to find the radius is to repeat part 54, but use the point (1.-4) rather than (-5,8). Do this to obtain the same answer found in part 54.
Let (X7,71) = (1, - 4) and (x2.Y2) be the coordinates of the center. Substitute the correct values into the distance formula.
(x2 - 1)2 + (y2 - y)2 = V(-2-1)2+(2-(-4))?
(Type the terms of your expression in the same order as they appear in the original expression. Do not evaluate.)
56. There is yet another way to find the radius. Because the radius is half the diameter, it can be found by finding half the length of the diameter. Using the
endpoints of the diameter given in the problem, find the radius in this manner. The same answer found in part 54 should once again be obtained.
Let (x4,91) = (-5,8) and (x2.72) = (1, - 4). Substitute the correct values into the distance formula.
V (1+5
(x2 – x1)2 + (92 - y1)?
+ (-4-8)
2
2
(Type the terms of your expression in the same order as they appear in the original expression. Do not evaluate)
57. Using the center found in part 53 and the radius found in parts 54-56, give the center-radius form of the equation of the circle.
(x + 2)2 + (y + 2)2 = 45 (Type an equation Simplify your answer)
58. Use the method described in parts 53-57 to find the center-radius form of the equation of the circle with diameter having endpoints (3,-9) and (-9,7).
(Type an equation. Simplify your answer)