+0

# The standard form of the equation of a circle is (x−4)2+(y−2)2=9.

0
277
1
+175

The standard form of the equation of a circle is (x−4)2+(y−2)2=9.

What is the general form of the equation?

x2+y2+8x+4y+11=0

x2+y2−8x−4y−29=0

x2+y2+8x+4y−29=0

x2+y2−8x−4y+11=0

jbouyer  May 15, 2017

#1
+5565
+3

(x - 4)2 + (y - 2)2 = 9

We want to multiply this out.

(x - 4)(x - 4)   + (y - 2)(y - 2) = 9

(x2 - 8x + 16) + (y2 - 4y + 4) = 9

x2 - 8x + 16 + y2 - 4y + 4 = 9

Rearrange and subtract 9 from both sides.

x2 + y2 - 8x - 4y + 16 + 4 - 9 = 0

x2 + y2 - 8x - 4y + 11 = 0

hectictar  May 15, 2017
Sort:

#1
+5565
+3

(x - 4)2 + (y - 2)2 = 9

We want to multiply this out.

(x - 4)(x - 4)   + (y - 2)(y - 2) = 9

(x2 - 8x + 16) + (y2 - 4y + 4) = 9

x2 - 8x + 16 + y2 - 4y + 4 = 9

Rearrange and subtract 9 from both sides.

x2 + y2 - 8x - 4y + 16 + 4 - 9 = 0

x2 + y2 - 8x - 4y + 11 = 0

hectictar  May 15, 2017

### 7 Online Users

We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners.  See details