Additional Mathematics Lines and circles
Section 3: The equation of a circle
Section test
1. Which one of the following equations does not represent a circle?
(a)
(c)
(e)
2x2 + y2  16 = 0.
x2 + y2  2x + 9y = 0.
I don’t know
(b)
(d)
2x2 + 2y2  3x + 5y  7 = 0.
x2 + y2  6 = 0.
2. What is the centre and radius of the circle x2 + y2 = 8?
(a)
(c)
(e)
Centre (8,8) and radius 64.
(b)
(d)
Centre (2 2, 2 2) and radius 8.
I don’t know
Centre (0,0) and radius 2 2.
Centre (0,0) and radius 4.
3. What is the centre and radius of the circle (x 1)2 + (y 1)2 = 9?
(a)
(c)
(e)
Centre (0,0) and radius 3.
Centre (3,3) and radius 9.
I don’t know
(b)
(d)
Centre (1,1) and radius 4.5.
Centre (1,1) and radius 3.
4. Which of the following points lies on the circle (x 4)2 + (y 3)2 = 25?
O (0, 0), A (4, 3), B (5, 5), C (8, 6)
(a)
(c)
(e)
All of them
Just A
I don’t know
(b)
(d)
O and C
O, A and C
5. What are the centre and radius of the circle x2 + y2  2x + 6y + 6 = 0?
(a)
(c)
Centre (1, 3) and radius 2.
Centre (2, 6) and radius 2.
(e)
I don’t know
(b)
Centre (1,1) and radius 2.
(d)
Centre (0,0) and radius 6.
6. A circle has centre (2, 5) and radius 6. Which one of the following is its equation?
(a)
(c)
(e)
x2 + y2  2x  5y  6 = 0
x2 + y2  4x  10y  36
I don’t know
(b)
(d)
1 of 2
x2 + y2  4x  10y = 7
x2 + y2  2x  5y  7 = 0
05/06/13 © MEI
AM Lines & circles 3 section test
7. A circle has centre (3, 2) and passes through the origin. Which one of the following is its
equation?
(a)
(c)
(e)
x2 + y2  6x  4y = 13
x2 + y2  3x  2y  13
I don’t know
(b)
(d)
x2 + y2  6x  4y = 0
x2 + y2  6x  4y = 52
8. A circle has centre (2, 1) and passes through (4, 1). Which one of the following is its
equation?
(a)
(c)
(e)
x2 + y2  4x y = 31
x2 + y2  4x y  35
I don’t know
(b)
(d)
x2 + y2  6x  4y + 3 = 0
x2 + y2 4x  2y = 33
9. Which of the following points lie inside the circle x2 + y2 8x  10y  5 = 0?
O (0, 0), A (4, 5), B (8, 1), C (5, 6)
(a)
(c)
(e)
O, A and C
O and A
I don’t know
(b)
(d)
B and C
A, B and C
10. A circle has the points A (2, 3) and B (4, 1) at the ends of a diameter. Which one of the
following is its equation?
(a)
(c)
(e)
x2 + y2 6x 2y = 0
x2 + y2  2x  2y  21
I don’t know
(b)
(d)
2 of 2
x2 + y2  2x  2y = 15
x2 + y2 2x  2y = 11
05/06/13 © MEI