Use completing the square to rewrite the equation in the form (x-h)^2 +(y-k)^2 = r^2. state the center (h, k) and radius r of the circle 2x^2 + 2y^2 + 4x + 8y - 20 = 0

The equation is (x + 1)^2 + (y + 2)^2 = 15

Center is at  (-1, -2) and radius = √15

Step-by-step explanation:

2x^2 + 2y^2 + 4x + 8y - 20 = 0

Divide through by 2:-

x^2 + y^2 + 2x + 4y - 10 = 0

x^2 + 2x + y^2 + 4x = 10

Completing the square on the x and y terms:-

(x + 1)^2 - 1 + (y + 2)^2 - 4 = 10

(x + 1)^2 + (y + 2)^2 = 10 + 1 + 4

(x + 1)^2 + (y + 2)^2 = 15    

to find the total number of combinations, multiply the quantity of each item by each other:

2 pairs of shoes x 3 pairs of shorts = 6 different combinations.

18.75 gallons

step-by-step explanation: