Question

The equation of a circle is (x + 7)2 + (y + 2)2 = 49. Determine the length of the diameter.
(step by step please so i can learn)

Answer 1

Do you know the equation of circle?

Answer 2

(x-h)^2+(y-k)^2=r^2 @mikurout

Answer 3

Here r stands for which term?

Answer 4

radius?
@mikurout

Answer 5

Yes

Answer 6

radius r = 7
diameter,d = 2r
=2(7)
=14
Source:www.mathskey.com

Answer 7

Now you know the value of radius.

Answer 8

As r^2 = 49
so r = \[\sqrt{49}\]
=7

Answer 9

so if the formula says "(x-h)' what causes the minus to change to addition? @mikurout

Answer 10

It is the position of center

Answer 11

so for example if the centers coordinates are (6,7) would that be addition or subtraction

Answer 12

@mikurout

Answer 13

substraction

Answer 14

so when the cordinates are positive you subtract and when theyre negative youu add? ok i get it now thanks @mikurout

Answer 15

Yes

Answer 16

It is just the distance formula , that we are using for finding out the distance between center and any point on the circle.