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

@emcrazy14

Answer 2

@AravindG @agent0smith @B.Sanders @Bsho1997

Answer 3

the center of what?

Answer 4

its to find the center of a circle

Answer 5

ok

Answer 6

so do you know how i solve this

Answer 7

x^2 + 2x + y^2 + 4y = 20
(x^2 + 2x) + (y^2 + 4y) = 20
(x^2 + 2x + 1 - 1) + (y^2 + 4y + 4 - 4) = 20
((x^2 + 2x + 1) - 1) + ((y^2 + 4y + 4) - 4) = 20
((x+1)^2 - 1) + ((y+2)^2 - 4) = 20
(x+1)^2 - 1 + (y+2)^2 - 4 = 20
(x+1)^2 + (y+2)^2 - 5 = 20
(x+1)^2 + (y+2)^2 = 20 + 5
(x+1)^2 + (y+2)^2 = 25
(x-(-1))^2 + (y-(-2))^2 = 25
This equation is in the form (x-h)^2 + (y-k)^2 = r^2 where (h,k) = (-1,-2) and r = 5

This is a circle with "The center is located at (-1, -2), and the radius is 5" (which is chioce c)

Answer 8

thank you!

Answer 9

your welcome

Answer 10

A circle is represented by the equation below:

(x + 8)2 + (y − 3)2 = 100

Which statement is true?

Answer 11

The circle is centered at (−8, 3) and has a radius of 20.

The circle is centered at (8, −3) and has a diameter of 20.

The circle is centered at (8, −3) and has a radius of 20.

The circle is centered at (−8, 3) and has a diameter of 20.

Answer 12

well using the equation of a circle which is (x−h)^2+(y−k)^2=r^2
so your center (-8,3) and your radius would be 10
the diameter for a circle is the radius times 2
so the diameter would be 20

Answer 13

okay so D

Answer 14

thats what i just got when I solved it

Answer 15

lol yup yup