Answer:
Option C
Step-by-step explanation:
The standard form of equation of a cirle is:
(x-h)^2+ (y-k)^2=r^2
In the given question as the point is given and the radius of circle is given:
So,
(h,k)=(2,-1)
and
r=3
Here,
h=2
k= -1
Putting the values of h,k and r in standard form
(x-2)^2+ (y-(-1))^2=(3)^2
(x-2)^2+ (y+1)^2=(3)^2
So the equation of circle is:
(x-2)^2+ (y+1)^2=9(3)^2
Option C is the correct answer ..
Answer:
For number 2 the answer is 8/6=20/15
The answer for 3 is 12:26
Step-by-step explanation:
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Answer:
centre = (- 3, - 2) , radius = 1
Step-by-step explanation:
The equation of a circle in standard form is
(x - h)² + (y - k)² = r²
where (h, k) are the coordinates of the centre and r is the radius
Given
x² + 6x + y² + 4y + 12 = 0 ( subtract 12 from both sides )
x² + 6x + y² + 4y = - 12
Use the method of completing the square on the x and y terms
add ( half the coefficient of the x/ y terms )² to both sides
x² + 2(3)x + 9 + y² + 2(2)y + 4 = - 12 + 9 + 4
(x + 3)² + (y + 2)² = 1 ← in standard form
with centre = (- (- 3), - (- 2)) and r² = 1, that is
centre = (- 3, - 2) and radius = 1
