20. What is the equation of a circle with a center at (-4,-8) and a radius of 1.9?

(x + 4) ^2 + (y + 8) ^2 = 1.9^2 = 3.61

Step-by-step explanation:

the standard equation of a circle with center at (h, k) and with radius r is

(x - h) ^2 + (y - k) ^2 = r^2. Here, (-4, - 8) is (h, k) and 1.9 is r.

Then the desired equation is:

(x + 4) ^2 + (y + 8) ^2 = 1.9^2 = 3.61