1.
Write the standard form of the equation of the circle that is tangent to the
y
-axis and has its center at (5, –3).
A.
(
x
+ 5)
2
+ (
y
– 3)
2
= 25
B.
(
x
– 5)
2
+ (
y
+ 3)
2
= 5
C.
(
x
+ 5)
2
+ (
y
– 3)
2
= 5
D.
(
x
– 5)
2
+ (
y
+ 3)
2
= 25
Hint
2.
The equation of a circle is 3
x
2
+ 3
y
2
– 6
x
+ 12
y
– 24 = 0. Find its center and radius.
A.
(–1, 2); 13
B.
(1, –2); 13
C.
(–1, 2);
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
= 10
C.
(
x
+ 3)
2
+ (
y
+ 2)
2
= 5
D.
(
x
+ 3)
2
+ (
y
+ 2)
2
= 13
Hint
4.
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.
(
x
+ 4)
2
+ (
y
– 1)
2
= 18
B.
C.
D.
(
x
– 4)
2
+ (
y
+ 1)
2
= 18
Hint
5.
Write the equation of a circle that has a diameter with endpoints at (1, 0) and (5, 4).
A.
(
x
+ 3)
2
+ (
y
- 2)
2
= 64
B.
(
x
- 3)
2
+ (
y
- 2)
2
= 64
C.
(
x
+ 3)
2
+ (
y
+ 2)
2
= 8
D.
(
x
- 3)
2
+ (
y
- 2)
2
= 8
Hint