What are the coordinates of the center and the
length of the radius of the circle whose equation is
x2 + y2 = 8x - 6y + 39?

The coordinate of the center is (4,-3)

radius = 8

Step-by-step explanation:

Given ;

re - arranging , we have

comparing with the general equation

This means that

also

The coordinate of the center is (-g,-f)

Therefore;

the coordinate of the center = (4,-3)

the formula for calculating r is given by:

METHOD 2

using completing the square method , we have

completing the square , we have

comparing with the general equation

where a and b are the coordinate of the center , that is

the coordinate of the center is ( 4 , -3)

(2x + 16) + (x) = 180

step-by-step explanation:

given,

abcd is a quadrilateral inscribed in a circle

angle a is labeled x plus 16, (x + 16)

angle b is labeled x degrees, (x)

angle c is labeled 6x minus 4, (6x – 4)

angle d is labeled 2x plus 16, (2x + 16)

what equation can be used to solve for angle b?

we know that the sum of the opposite angles of a simple quadrilateral inscribed in a circle is 180 degrees.

angle b is opposite angle d

therefore, angle b + angle d = 180

(x) + (2x + 16) = 180 

same as (2x + 16) + (x) = 180

answer: 8d

step-by-step explanation:

45+5= 50+5=55+5=60