Find the equation of a circle with a center at (7,2) and a point on the circle at (-2,-5).
( x - 7 )^2 + ( y - 2 )^2 = sqrt 130
( x + 7 )^2 - ( y + 2 )^2 = sqrt 130
( x - 7 )^2 + ( y - 2 )^2 = 130
( x + 7 )^2 - ( y + 2 )^2 = 130

(x - 7)² + (y - 2)² = 130

Step-by-step explanation:

The first step is finding the length of the radius.

r² = (2 - -5)² + (7 - -2)²

    = 7² + 9²

    = 49 + 81

   = 130

The general equation of a circle is:

(x - a)² + (y - b)² = r²

Where (a, b) is the coordinate of the center and r is the radius.

∴ The equation of the required circle is;

 (x - 7)² + (y - 2)² = 130

x= -3 and

step-by-step explanation:

to find the roots of a cubic, use division or factoring to find the factors then set equal to 0. as this is a difference of cubes, it factors into

where a is the cube root of .

here   this is 27 and the cube root of 27 is 3. so we write using the form:

.

set each factor to 0 and solve for x.

x-3=0

x=3

the quadratic expression does not factor and must be solved using the quadratic formula.

where a = 1, b=3, and c=9

this cubic has two complex roots.