Question

What is the radius of a circle whose equation is x2+y2+8x−6y+21=0? Please just copy and paste this into brainly, I ran out of skips

Answer 1

Answer: 2

Step-by-step explanation:

Answer 2

Answer:

The Radius of the circle of center (-4, 3) is 2.

Radius = 2

Step-by-step explanation:

This is the general form:

$x^2+y^2+8x-6y+21=0$

Let's convert this to standard form:

$x^2+y^2+8x-6y+21=0$

$x^2+y^2+8x-6y=-21$

Group/organize $x$ and $y$ terms:

$x^2+8x+y^2-6y=-21$

$(x^2+8x)+(y^2-6y)=-21$

Now, let's begin the process to complete the square in both parentheses.

$(x^2+8x+16)+(y^2-6y+9)=-21+16+9$

$(x+4)^2+(y-3)^2=4$