X2 + y2 - 20x +14y + 28 = 0 is a circle. What is the radius of this circle?

11

Step-by-step explanation:

observe the equation equivalent to

x² – 20x + 100 + y² + 14y + 49 = 121

(x–10)² + (y+7)² = 11²

so the circle has radius 11

i think is g(1)=-1.

hope that i can

a28=58

step-by-step explanation:

a1=a1+(n-1)d

a28= 4+ (28-1)2

a28=4+(27)(2)

a28=4+54

a28=58