Question

Using the following equation, find the center and radius:

x2 + 2x + y2 + 4y = 20

The center is located at (1, 2), and the radius is 25.
The center is located at (−1, 2), and the radius is 25.
The center is located at (−1, −2), and the radius is 5.
The center is located at (1, 2), and the radius is 5.

Answer 1

Look at the equation and, Convert it to the sum of two squares by using a simple method

After doing that you'll get the equation

\[(x+1)2+(y+2)2=25\]

Next Look up the formula for a circle with a center that is not at ( 0,0 ) in standard form

The rest should come easy

Answer 2

Hmmm idk

Answer 3

Formula:

\(\bf{(x-h)^{2} + (y-k)^{2}=r^{2}}\)

`(h,k)` is your center
`r` is your radius

@xxemilianaxx provided with your equation already, you should come by the answer quite easily with the explanation and provided formula.

Answer 4

So the answer would be " The center is located at (−1, 2), and the radius is 25. which is option B.)

Answer 5

Your total is `25` not `25^2` you need to find `r`. To do this you need to find the square root of `25`.

Also, `x` is correct as `-1` but keep in mind if you have `y-k` and your equation is `y+2` then that means that `2` is `-2`

Answer 6

Hmmmm is it would be " The center is located at (−1, −2), and the radius is 5."

Answer 7

Correct!

Answer 8

That's correct