Question

Write the standard equation for the circle.

center (-6 9) r=3
A. (X-9)^2+(y+6)^2=9
B. (X+6)^2+(Y-9)^2=3
C. (X-6)^2+(Y+9)^2=3
D. (X+6)^2+(Y-9)^2=9

Find the center and radius of the circle with equation (x+2)^2+(y+10)2=4
A. Center (-2, -10); r=2
B. Center (2, 10); r=4
C. Center (-2, -10); r=4
D. Center (10, 2); r=2

What is the equation of the fircle with center 3,5 that passes through the point (-4, 10)?
A. (x-3)^2 + (y-5)^2 = 226
B. (x+4)^2 + (y-10)^2 = 74
C. (x+4)^2 + (y-10)^2 = 226
D. (x+3)^2 + (y-5)^2 = 74

What is the equation of the circle with center (0,0) that passes through the point (5,-4)?
A. x^2 + y^2 = 41
B. (x+4)^2 + (y+4)^2 = 41
C. (x-5)^2 + (y+4)^2 = 9
D. x^2 + y^2 = 9

Answer 1

The equation of the circle with center (h, k) and radius r is
.. (x -h)^2 +(y -k)^2 = r^2

1. selection D matches the specification of the circle

2. selection A matches the given equation

3. None of the offered selections matches
.. (x -3)^2 +(y -5)^2 = 74

4. selection A matches the requirements