Question

Determine the center and radius of the circle described by the question. (X+2)

Answer 1

The question is incomplete, I will however explain, with an illustration, how to determine the center and radius of a circle.

Step-by-step explanation:

The standard equation of a circle is given as:

(x - a)² + (y - b)² = r² ........................(1)

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

An expression can be given for us to find the center and the radius of the circle.

Suppose we were given the expression:

x² + y² - 10x + 4y - 7 = 0.....................(2)

To find the center and the radius, it is left for us to rewrite (2) in the form of (1).

Rearranging (2), we have

(x² - 10x) + (y² + 4y) = 7

Completing the squares of each bracket

(x² - 10x + 25 - 25) + (y² + 4y + 4 - 4) = 7

(x² - 10x + 25) + (y² + 4y + 4) - 25 - 4 = 7

(x² - 10x + 25) + (y² + 4y + 4) - 29 = 7

(x - 5)² + (y + 2)² = 7 + 29

(x - 5)² + (y + 2)² = 36

Or

(x - 5)² + (y + 2)² = 6² .....................(3)

Comparing (3) with one, we see that

a = 5, b = -2, and r = 6

Therefore it is a circle centered at (5, -2) with a 6 unit radius.