Answer:
x² + y² + 4x - 2y + 1 = 0
Step-by-step explanation:
The equation of a circle is given by the general equation;
(x-a)² + (y-b)² = r² ; where (a,b) is the center of the circle and r is the radius.
In this case; the center is (-2,1)
We can get radius using the formula for magnitude; √((x2-x1)² + (y2-y1)²)
Radius = √((-4- (-2))² + (1-1)²)
= 2
Therefore;
The equation of the circle will be;
(x+2)² + (y-1)² = 2²
(x+2)² + (y-1)² = 4
Expanding the equation;
x² + 4x + 4 + y² -2y + 1 = 4 subtracting 4 from both sides;
x² + 4x + y² - 2y + 4 + 1 -4 = 0
= x² + y² + 4x - 2y + 1 = 0
(-8)^2
(-8)(-8)
64
Hope this helps!
Answer:
5
Step-by-step explanation:
The radius is a distance on a circle from the center to a point on the circle.
We have both of these points describe here in this definition. Using the distance formula will give us the radius.
The difference between 1 and -3 is 1-(-3)=4.
The difference between 5 and 2 is 5-2=3.
