Write an equation of a circle centered at (-2, -8) with a diameter of 2.
A) $( x + 2 ) ^ { 2 } + ( y + 8 ) ^ { 2 } = 1$
B) $( x + 2 ) ^ { 2 } + ( y + 8 ) ^ { 2 } = 4$
C) $( x - 2 ) ^ { 2 } + ( y - 8 ) ^ { 2 } = 4$
D) $( x - 2 ) ^ { 2 } + ( y - 8 ) ^ { 2 } = 1$

Question

Write an equation of a circle centered at (-2, -8) with a diameter of 2. 
A) $( x + 2 ) ^ { 2 } + ( y + 8 ) ^ { 2 } = 1$
B) $( x + 2 ) ^ { 2 } + ( y + 8 ) ^ { 2 } = 4$
C) $( x - 2 ) ^ { 2 } + ( y - 8 ) ^ { 2 } = 4$
D) $( x - 2 ) ^ { 2 } + ( y - 8 ) ^ { 2 } = 1$

Quizplus · Accepted Answer

The equation of a circle is $(x - h)^2 + (y - k)^2 = r^2$, where $(h, k)$ is the center and $r$ is the radius. Given the center $(-2, -8)$ and diameter $2$, the radius is $1$. Substituting $h = -2$, $k = -8$, and $r = 1$ gives $(x + 2)^2 + (y + 8)^2 = 1$.

Write an Equation of a Circle Centered at (-2, -8) (x+2)2+(y+8)2=1( x + 2 ) ^ { 2 } + ( y + 8 ) ^ { 2 } = 1(x+2)2+(y+8)2=1

Write an Equation of a Circle Centered at (-2, -8) $( x + 2 ) ^ { 2 } + ( y + 8 ) ^ { 2 } = 1$