Question 4 (essay worth 10 points) (09.04 mc) using the following equation, find the center and radius of the circle. you must show all work and calculations to receive credit. x2 − 4x + y2 + 8y = −4

Half the x-coefficient is -2, and the square of that is 4.half the y-coefficient is 4, and the square of that is 16.adding 4+16 to the equation gives    (x² -4x +4) + (y² +8y +16) = 16    (x-2)² + (y+4)² = 4²comparing this to the standard form    (x-h)² + (y-k)² = r²we find the center (h, k) to be (2, -4) and the radius r to be 4.