Question

(x + 55)^2+(y - 11.5)^2 = 121
a circle in the xy - plane has the equation shown. what is the length of the diameter of the circle?

Explanation:

Step1: Recall circle - equation form

The standard form of a circle equation is $(x - a)^2+(y - b)^2=r^2$. Here, $r^2 = 121$.

Step2: Find the radius

If $r^2=121$, then $r=\sqrt{121}=11$.

Step3: Calculate the diameter

The diameter $d = 2r$, so $d = 2\times11 = 22$.

Answer:

22