Given the equation of the
circle:
x^2 + y^2 - 8x + 12y =
12
We need to rewrite the equation into the standard form
in order to determine the radius.
==> (x-a)^2 +
(y-b)^2 = r^2
Then we will need to complete the
square.
==> x^2 - 8x + 16 -16 + y^2 + 12y + 36 -36 =
12
==> (x-4)^2 + (y+6)^2 = 12 + 36 +
16
==. (x-4)^2 + 9y+6)^2 =
64
==> (x-4)^2 + (y+6)^2 =
8^2
Then the radius is r=
8.
Now we will calculate the
area.
==> A= r^2 * pi = 8^2 * pi = 64*pi =
201.06
Then the area of the circle is 64pi =
201.06 square units.
No comments:
Post a Comment