Using the following equation, find the center and radius of the circle. you must show all work and calculations to receive credit. x2 + 2x + y2 + 4y = 20

if you can explain this in an easy way for me to understand ill make u the top !

Centre = (-1, -2); r = 5

Step-by-step explanation:

The centre-radius form for the equation of a circle is

(x - h)² + (y - k)² = r²  

where r is the radius and the centre is at (h, k) .

Your equation is

x² + 2x + y² + 4y = 20  

Step 1. Complete the squares for x and y

Square half the coefficients of x and y and add them to each side of the equation

(x² + 2x + 1²) + (y² + 4y + 2²) = 20 + 1² + 2²

Step 2. Write the left-hand side as squares of binomials

(x + 1)² + (y+ 2)² = 20 + 1² + 2²

Step 3. Convert the right-hand side to a square

(x + 1)² + (y + 2)² = 20 + 1 + 4  

(x + 1)² + (y + 2)² = 25

(x + 1)² + (y + 2)² =   5²  

h = -1; k = -2; r = 5

The graph below shows that this is the equation for a circle with

centre (-1, -2) and radius 5.

answer: b

step-by-step explanation: